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1.
Sci Rep ; 14(1): 10539, 2024 05 08.
Article En | MEDLINE | ID: mdl-38719941

Abnormal angiogenesis leads to tumor progression and metastasis in colorectal cancer (CRC). This study aimed to elucidate the association between angiogenesis-related genes, including VEGF-A, ANGPT-1, and ANGPT-2 with both metastatic and microsatellite alterations at selected tetranucleotide repeats (EMAST) subtypes of CRC. We conducted a thorough assessment of the ANGPT-1, ANGPT-2, and VEGF-A gene expression utilizing publicly available RNA sequencing and microarray datasets. Then, the experimental validation was performed in 122 CRC patients, considering their disease metastasis and EMAST+/- profile by using reverse transcription polymerase chain reaction (RT-PCR). Subsequently, a competing endogenous RNA (ceRNA) network associated with these angiogenesis-related genes was constructed and analyzed. The expression level of VEGF-A and ANGPT-2 genes were significantly higher in tumor tissues as compared with normal adjacent tissues (P-value < 0.001). Nevertheless, ANGPT-1 had a significantly lower expression in tumor samples than in normal colon tissue (P-value < 0.01). We identified a significantly increased VEGF-A (P-value = 0.002) and decreased ANGPT-1 (P-value = 0.04) expression in EMAST+ colorectal tumors. Regarding metastasis, a significantly increased VEGF-A and ANGPT-2 expression (P-value = 0.001) and decreased ANGPT-1 expression (P-value < 0.05) were established in metastatic CRC patients. Remarkably, co-expression analysis also showed a strong correlation between ANGPT-2 and VEGF-A gene expressions. The ceRNA network was constructed by ANGPT-1, ANGPT-2, VEGF-A, and experimentally validated miRNAs (hsa-miR-190a-3p, hsa-miR-374c-5p, hsa-miR-452-5p, and hsa-miR-889-3p), lncRNAs (AFAP1-AS1, KCNQ1OT1 and MALAT1), and TFs (Sp1, E2F1, and STAT3). Network analysis revealed that colorectal cancer is amongst the 82 significant pathways. We demonstrated a significant differential expression of VEGF-A and ANGPT-1 in colorectal cancer patients exhibiting the EMAST+ phenotype. This finding provides novel insights into the molecular pathogenesis of colorectal cancer, specifically in EMAST subtypes. Yet, the generalization of in silico findings to EMAST+ colorectal cancer warrants future experimental investigations. In the end, this study proposes that the EMAST biomarker could serve as an additional perspective on CMS4 biology which is well-defined by activated angiogenesis and worse overall survival.


Angiopoietin-1 , Angiopoietin-2 , Colorectal Neoplasms , Gene Expression Regulation, Neoplastic , Neovascularization, Pathologic , Vascular Endothelial Growth Factor A , Humans , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Colorectal Neoplasms/metabolism , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Angiopoietin-1/genetics , Angiopoietin-1/metabolism , Angiopoietin-2/genetics , Angiopoietin-2/metabolism , Male , Female , Middle Aged , Neoplasm Metastasis , Aged , Microsatellite Repeats/genetics , Gene Expression Profiling , Gene Regulatory Networks , Angiogenesis
2.
BMC Plant Biol ; 24(1): 355, 2024 May 09.
Article En | MEDLINE | ID: mdl-38724929

BACKGROUND: Jackfruit (Artocarpus heterophyllus) is an economically valuable fruit tree in Uganda. However, the production of jackfruit in Uganda is low. Additionally, because of deforestation, genetic erosion of the resource is predicted before its exploitation for crop improvement and conservation. As a prerequisite for crop improvement and conservation, 100 A. heterophyllus tree isolates from the Kayunga and Luwero districts in Uganda were characterized using 16 morphological and 10 microsatellite markers. RESULTS: The results from the morphological analysis revealed variations in tree height, diameter at breast height (DBH), and crown diameter, with coefficient of variation (CV) values of 20%, 41%, and 33%, respectively. Apart from the pulp taste, variation was also observed in qualitative traits, including tree vigor, trunk surface, branching density, tree growth habit, crown shape, leaf blade shape, fruit shape, fruit surface, flake shape, flake color, flake flavor and pulp consistency/texture. Genotyping revealed that the number of alleles amplified per microsatellite locus ranged from 2 to 5, with an average of 2.90 and a total of 29. The mean observed (Ho) and expected (He) heterozygosity were 0.71 and 0.57, respectively. Analysis of molecular variance (AMOVA) indicated that 81% of the variation occurred within individual trees, 19% among trees within populations and 0% between the two populations. The gene flow (Nm) in the two populations was 88.72. The results from the 'partitioning around medoids' (PAM), principal coordinate analysis (PCoA) and genetic cluster analysis further revealed no differentiation of the jackfruit populations. The Mantel test revealed a negligible correlation between the morphological and genetic distances. CONCLUSIONS: Both morphological and genetic analyses revealed variation in jackfruit within a single interbreeding population. This diversity can be exploited to establish breeding and conservation strategies to increase the production of jackfruit and hence boost farmers' incomes. However, selecting germplasm based on morphology alone may be misleading.


Artocarpus , Microsatellite Repeats , Uganda , Artocarpus/genetics , Artocarpus/anatomy & histology , Microsatellite Repeats/genetics , Fruit/genetics , Fruit/anatomy & histology , Fruit/growth & development , Genetic Variation , Genotype
3.
Sci Rep ; 14(1): 10447, 2024 05 07.
Article En | MEDLINE | ID: mdl-38714726

Polyandry, the practice of females mating with multiple males, is a strategy found in many insect groups. Whether it increases the likelihood of receiving beneficial genes from male partners and other potential benefits for females is controversial. Strepsiptera are generally considered monandrous, but in a few species females have been observed copulating serially with multiple males. Here we show that the offspring of a single female can have multiple fathers in two Strepsiptera species: Stylops ovinae (Stylopidae) and Xenos vesparum (Xenidae). We studied female polyandry in natural populations of these two species by analysis of polymorphic microsatellite loci. Our results showed that several fathers can be involved in both species, in some cases up to four. Mating experiments with S. ovinae have shown that the first male to mates with a given female contributes to a higher percentage of the offspring than subsequent males. In X. vesparum, however, we found no significant correlation between mating duration and offspring contribution. The prolonged copulation observed in S. ovinae may have the advantage of reducing competition with sperm from other males. Our results show that monandry may not be the general pattern of reproduction in the insect order Strepsiptera.


Insecta , Microsatellite Repeats , Sexual Behavior, Animal , Spermatozoa , Animals , Male , Female , Sexual Behavior, Animal/physiology , Spermatozoa/physiology , Insecta/physiology , Microsatellite Repeats/genetics , Reproduction/physiology
4.
PLoS One ; 19(5): e0289351, 2024.
Article En | MEDLINE | ID: mdl-38696386

In this study, an extensive analysis of microsatellite markers (Single Tandem Repeats-STRs) in Penaeus vannamei was conducted at an advanced level. The markers were thoroughly examined, characterized, and specific markers located within coding regions were identified. Out of a total of 306 STRs, 117 were classified as perfect markers based on their single repeat motif. Among these perfect markers, 62 were found to be associated with predicted coding genes (mRNA), which were involved in various functions such as binding, catalytic activity, ATP-dependent activity, transcription, structural and molecular regulation. To validate the accuracy of the findings, a sample of nine markers was subjected to in vitro testing, which confirmed the presence of polymorphisms within the population. These results suggest the existence of different protein isoforms within the population, indicating the potential of these markers for application in both population and phenotype-genotype association studies. This innovative approach opens up new possibilities for investigating the impact of genomic plasticity in populations of P. vannamei.


Microsatellite Repeats , Penaeidae , Animals , Microsatellite Repeats/genetics , Penaeidae/genetics , Genome , Polymorphism, Genetic , Open Reading Frames/genetics
5.
Sci Rep ; 14(1): 11071, 2024 05 14.
Article En | MEDLINE | ID: mdl-38745036

The southern coast of Africa is one of the few places in the world where water temperatures are predicted to cool in the future. This endemism-rich coastline is home to two sister species of kelps of the genus Ecklonia maxima and Ecklonia radiata, each associated with specific thermal niches, and occuring primarily on opposite sides of the southern tip of Africa. Historical distribution records indicate that E. maxima has recently shifted its distribution ~ 70 km eastward, to sites where only E. radiata was previously reported. The contact of sister species with contrasting thermal affinities and the occurrence of mixed morphologies raised the hypothesis that hybridization might be occurring in this contact zone. Here we describe the genetic structure of the genus Ecklonia along the southern coast of Africa and investigate potential hybridization and cryptic diversity using a combination of nuclear microsatellites and mitochondrial markers. We found that both species have geographically discrete genetic clusters, consistent with expected phylogeographic breaks along this coastline. In addition, depth-isolated populations were found to harbor unique genetic diversity, including a third Ecklonia lineage. Mito-nuclear discordance and high genetic divergence in the contact zones suggest multiple hybridization events between Ecklonia species. Discordance between morphological and molecular identification suggests the potential influence of abiotic factors leading to convergent phenotypes in the contact zones. Our results highlight an example of cryptic diversity and hybridization driven by contact between two closely related keystone species with contrasting thermal affinities.


Genetic Variation , Kelp , Phylogeny , Kelp/genetics , Kelp/classification , Phylogeography , Microsatellite Repeats/genetics , Hybridization, Genetic , DNA, Mitochondrial/genetics , Africa, Southern
6.
Front Cell Infect Microbiol ; 14: 1366563, 2024.
Article En | MEDLINE | ID: mdl-38716192

Background: Routine surveillance for antimalarial drug resistance is critical to sustaining the efficacy of artemisinin-based Combination Therapies (ACTs). Plasmodium falciparum kelch-13 (Pfkelch-13) and non-Pfkelch-13 artemisinin (ART) resistance-associated mutations are uncommon in Africa. We investigated polymorphisms in Plasmodium falciparum actin-binding protein (Pfcoronin) associated with in vivo reduced sensitivity to ART in Nigeria. Methods: Fifty-two P. falciparum malaria subjects who met the inclusion criteria were followed up in a 28-day therapeutic efficacy study of artemether-lumefantrine in Lagos, Nigeria. Parasite detection was done by microscopy and molecular diagnostic approaches involving PCR amplification of genes for Pf18S rRNA, varATS, telomere-associated repetitive elements-2 (TARE-2). Pfcoronin and Pfkelch-13 genes were sequenced bi-directionally while clonality of infections was determined using 12 neutral P. falciparum microsatellite loci and msp2 analyses. Antimalarial drugs (sulfadoxine-pyrimethamine, amodiaquine, chloroquine and some quinolones) resistance variants (DHFR_51, DHFR_59, DHFR_108, DHFR_164, MDR1_86, MDR1_184, DHPS_581 and DHPS_613) were genotyped by high-resolution melting (HRM) analysis. Results: A total of 7 (26.92%) cases were identified either as early treatment failure, late parasitological failure or late clinical failure. Of the four post-treatment infections identified as recrudescence by msp2 genotypes, only one was classified as recrudescence by multilocus microsatellites genotyping. Microsatellite analysis revealed no significant difference in the mean allelic diversity, He, (P = 0.19, Mann-Whitney test). Allele sizes and frequency per locus implicated one isolate. Genetic analysis of this isolate identified two new Pfcoronin SNVs (I68G and L173F) in addition to the P76S earlier reported. Linkage-Disequilibrium as a standardized association index, IAS, between multiple P. falciparum loci revealed significant LD (IAS = 0.2865, P=0.02, Monte-Carlo simulation) around the neutral microsatellite loci. The pfdhfr/pfdhps/pfmdr1 drug resistance-associated haplotypes combinations, (108T/N/51I/164L/59R/581G/86Y/184F), were observed in two samples. Conclusion: Pfcoronin mutations identified in this study, with potential to impact parasite clearance, may guide investigations on emerging ART tolerance in Nigeria, and West African endemic countries.


Antimalarials , Artemisinins , Drug Resistance , Malaria, Falciparum , Plasmodium falciparum , Plasmodium falciparum/genetics , Plasmodium falciparum/drug effects , Antimalarials/pharmacology , Antimalarials/therapeutic use , Nigeria , Humans , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Drug Resistance/genetics , Artemisinins/pharmacology , Artemisinins/therapeutic use , Mutation , Protozoan Proteins/genetics , Artemether, Lumefantrine Drug Combination/therapeutic use , Male , Microfilament Proteins/genetics , Female , Drug Combinations , Microsatellite Repeats/genetics , Genotype , Sequence Analysis, DNA , Recurrence , Polymorphism, Genetic , Adult
7.
PLoS One ; 19(5): e0302584, 2024.
Article En | MEDLINE | ID: mdl-38709757

The North African catfish (Clarias gariepinus) is a significant species in aquaculture, which is crucial for ensuring food and nutrition security. Their high adaptability to diverse environments has led to an increase in the number of farms that are available for their production. However, long-term closed breeding adversely affects their reproductive performance, leading to a decrease in production efficiency. This is possibly caused by inbreeding depression. To investigate the root cause of this issue, the genetic diversity of captive North African catfish populations was assessed in this study. Microsatellite genotyping and mitochondrial DNA D-loop sequencing were applied to 136 catfish specimens, collected from three populations captured for breeding in Thailand. Interestingly, extremely low inbreeding coefficients were obtained within each population, and distinct genetic diversity was observed among the three populations, indicating that their genetic origins are markedly different. This suggests that outbreeding depression by genetic admixture among currently captured populations of different origins may account for the low productivity of the North African catfish in Thailand. Genetic improvement of the North African catfish populations is required by introducing new populations whose origins are clearly known. This strategy should be systematically integrated into breeding programs to establish an ideal founder stock for selective breeding.


Catfishes , DNA, Mitochondrial , Genetic Variation , Inbreeding , Microsatellite Repeats , Animals , Catfishes/genetics , Thailand , Microsatellite Repeats/genetics , DNA, Mitochondrial/genetics , Genotype , Aquaculture , North African People
8.
Sci Rep ; 14(1): 10794, 2024 05 11.
Article En | MEDLINE | ID: mdl-38734757

The primary objective of Sustainable Development Goal target 2.5 established by the United Nations is to ensure the preservation of genetic diversity in domesticated animals. The ICAR-National Bureau of Animal Genetic Resources in India has been actively engaged in the conservation of cattle and buffalo bull semen for long-term storage. This present study aimed to assess the genetic diversity present in the conserved cattle bull semen, which would aid in determining the most suitable strategy for future conservation management. A total of 192 bull semen belonging to 19 cattle breeds were selected to evaluate genetic diversity using 17 pairs of FAO recommended microsatellite primers. Total 267 alleles were detected across all the samples which indicates substantial amount of allelic variation is being maintained in conserved bulls. Further, all cattle bulls semen conserved showed higher observed heterozygosity than expected heterozygosity which indicates excess genetic diversity in all the populations. The FST, F IT and FIS value across the loci and population is 0.146 ± 0.009, 0.054 ± 0.038, and - 0.105 ± 0.035, respectively, which suggests lack of inbreeding in conserved cattle bull semen. This study has established genetic diversity in conserved cattle semen samples to achieve sustainable development goals. In addition, it provides compelling evidence that the current approach for conserving cattle bull semen is heading in the correct direction.


Genetic Variation , Microsatellite Repeats , Animals , Cattle/genetics , Male , Microsatellite Repeats/genetics , India , Conservation of Natural Resources/methods , Sustainable Development , Semen , Alleles , Breeding
9.
Zhongguo Zhong Yao Za Zhi ; 49(3): 717-727, 2024 Feb.
Article Zh | MEDLINE | ID: mdl-38621875

Transcriptome sequencing was employed to mine the simple sequence repeat(SSR) locus information of Saposhnikovia divaricata and design specific primers, which aimed to provide a basis for the research on the genetic diversity of S. divaricata germplasm resources. The seed purity, 1 000-seed weight, germination rate, and seed vigor were determined. MISA was used to obtain the SSR locus information from 12 606 unigene longer than 1 kb in the transcriptome database. Forty-three pairs of SSR primers designed in Primer 3 were used to analyze the polymorphism of 28 S. divaricata samples of different sources. The results showed that there were differences in the seed purity, 1 000-seed weight, germination rate, vigor, and seed length and width among S. divaricata samples of different sources. Particularly, the germination rate and seed vigor had significant differences, and HB-ZJK1, NMG-CF4, NMG-BT, NMG-HLE1, and NMG-CF2 had significantly higher 1 000-seed weight, germination rate, and seed vigor than the samples of other sources. Among the 86 233 unigene, 12 606(14.62%) unigene contained 15 958 SSR loci, with one SSR locus every 5 009 bp on average. The SSR loci were mainly single nucleotide and dinucleotide repeats, which were dominated by G/C and TC/AG, respectively. All the primers were screened by using 28 S. divaricata sample from different habitats, and the primers corresponding to the amplification products with clear bands and stable polymorphism were obtained. The clustering results of the biological characteristics and genetic diversity of the 28 S. divaricata samples were basically consistent, and the samples of the same origin(HB-AG1, HB-AG2, HB-ZJK1, and HB-ZJK2) generally gathered together and had close genetic relationship. The SSRs in S. divaricata transcriptome has high frequency, rich types, and high polymorphism, which provides candidate molecular markers for the germplasm identification, genetic map construction, and molecular-assisted breeding.


Apiaceae , Transcriptome , Polymorphism, Genetic , Microsatellite Repeats/genetics , Apiaceae/genetics , Expressed Sequence Tags
10.
Mol Biol Rep ; 51(1): 534, 2024 Apr 20.
Article En | MEDLINE | ID: mdl-38642172

BACKGROUND: Thymus algeriensis Boiss. et Reut. is one of the most widespread North African species of the genus Thymus L. The species is subshrub growing primarily in subtropical biome of Morocco, Algeria, Tunisia and Libya. In Tunisia, the plant species is under high pressure of anthropogenic activities including over-collecting. The assessment of genetic diversity and population structure of T. algeriensis is a pioneer step to retrace its evolutionary history and to perform appropriate conservation strategies of the plant species. METHODS AND RESULTS: Seven wild populations growing, widely, in different bioclimatic zones were selected and analysed using two molecular markers systems. Fifteen Simple Sequence Repeats (SSRs) and fifteen Inter-Simple Sequence Repeats (ISSRs) were used to characterize genetically 140 different genotypes. The results showed a high molecular variation within populations and among the studied genotypes. The intra-populations genetic diversity revealed by SSRs was higher (P = 80.95%, Na = 2.143 and He = 0.364) than that based on ISSRs (P = 78.12%, Na = 1.632, He = 0.265 and I = 0.398). As demonstrated by inbreeding coefficients, a significant level of differentiation and a low level of gene flow were detected among studied populations (FST = 0.161 for SSRs and ΦST = 0.197 for ISSRs). Furthermore, the results of ISSRs marker suggest land strips as barriers in population genetic structure. While SSRs marker reflects a relatively structured bioclimatic patterns of studied populations. The Bayesian analysis showed a specific adaptation of populations to local environments. CONCLUSIONS: The used molecular markers (ISSRs and SSRs) seem to be effective in deciphering genetic polymorphism of Tunisian genotypes of T. algeriensis. Therefore, the genetic structure of the studied genotypes could constitute a starting point for further conservation, characterization and breeding programs.


Genetic Variation , North African People , Humans , Genetic Variation/genetics , Bayes Theorem , Polymorphism, Genetic/genetics , Biomarkers , Microsatellite Repeats/genetics
11.
BMC Genomics ; 25(1): 396, 2024 Apr 22.
Article En | MEDLINE | ID: mdl-38649816

BACKGROUND: While the size of chloroplast genomes (cpDNAs) is often influenced by the expansion and contraction of inverted repeat regions and the enrichment of repeats, it is the intergenic spacers (IGSs) that appear to play a pivotal role in determining the size of Pteridaceae cpDNAs. This provides an opportunity to delve into the evolution of chloroplast genomic structures of the Pteridaceae family. This study added five Pteridaceae species, comparing them with 36 published counterparts. RESULTS: Poor alignment in the non-coding regions of the Pteridaceae family was observed, and this was attributed to the widespread presence of overlong IGSs in Pteridaceae cpDNAs. These overlong IGSs were identified as a major factor influencing variations in cpDNA size. In comparison to non-expanded IGSs, overlong IGSs exhibited significantly higher GC content and were rich in repetitive sequences. Species divergence time estimations suggest that these overlong IGSs may have already existed during the early radiation of the Pteridaceae family. CONCLUSIONS: This study reveals new insights into the genetic variation, evolutionary history, and dynamic changes in the cpDNA structure of the Pteridaceae family, providing a fundamental resource for further exploring its evolutionary research.


Chloroplasts , DNA, Chloroplast , Genome, Chloroplast , Pteridaceae , Pteridaceae/classification , Pteridaceae/genetics , Genome, Chloroplast/genetics , Chloroplasts/genetics , DNA Transposable Elements/genetics , Phylogeny , DNA, Chloroplast/genetics , Evolution, Molecular , Genetic Variation , Microsatellite Repeats/genetics , Time Factors , Species Specificity
12.
Int J Mol Sci ; 25(7)2024 Mar 31.
Article En | MEDLINE | ID: mdl-38612732

Yellow catfish Tachysurus fulvidraco is an important commercial fish species in South Korea. However, due to their current declines in its distribution area and population size, it is being released from hatchery populations into wild populations. Hatchery populations also produced from wild broodstocks are used for its captive breeding. We reported 15 new microsatellite DNA markers of T. fulvidraco to identify the genetic diversity and structure of its hatchery and wild populations, providing baseline data for useful resource development strategies. The observed heterozygosity of the hatchery populations ranged from 0.816 to 0.873, and that of the wild populations ranged from 0.771 to 0.840. Their inbreeding coefficient ranged from -0.078 to 0.024. All populations experienced a bottleneck (p < 0.05), with effective population sizes ranging from 21 to infinity. Their gene structure was divided into two groups with STRUCTURE results of K = 2. It was confirmed that each hatchery population originated from a different wild population. This study provides genetic information necessary for the future development and conservation of fishery resources for T. fulvidraco.


Catfishes , Animals , Catfishes/genetics , Republic of Korea , Population Density , Fisheries , Microsatellite Repeats/genetics
13.
BMC Ecol Evol ; 24(1): 51, 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38654159

BACKGROUND: Different patterns of sex chromosome differentiation are seen in Palaeognathae birds, a lineage that includes the ratites (Struthioniformes, Rheiformes, Apterygiformes, Casuariiformes, and the sister group Tinamiformes). While some Tinamiform species have well-differentiated W chromosomes, both Z and W of all the flightless ratites are still morphologically undifferentiated. Here, we conducted a comprehensive analysis of the ZW differentiation in birds using a combination of cytogenetic, genomic, and bioinformatic approaches. The whole set of satDNAs from the emu (Dromaius novaehollandiae) was described and characterized. Furthermore, we examined the in situ locations of these satDNAs alongside several microsatellite repeats and carried out Comparative Genomic Hybridizations in two related species: the greater rhea (Rhea americana) and the tataupa tinamou (Crypturellus tataupa). RESULTS: From the 24 satDNA families identified (which represent the greatest diversity of satDNAs ever uncovered in any bird species), only three of them were found to accumulate on the emu's sex chromosomes, with no discernible accumulation observed on the W chromosome. The W chromosomes of both the greater rhea and the emu did not exhibit a significant buildup of either C-positive heterochromatin or repetitive DNAs, indicating their large undifferentiation both at morphological and molecular levels. In contrast, the tataupa tinamou has a highly differentiated W chromosome that accumulates several DNA repeats. CONCLUSION: The findings provide new information on the architecture of the avian genome and an inside look at the starting points of sex chromosome differentiation in birds.


Palaeognathae , Sex Chromosomes , Animals , Sex Chromosomes/genetics , Palaeognathae/genetics , Male , Female , Evolution, Molecular , Microsatellite Repeats/genetics , Biological Evolution , Comparative Genomic Hybridization
14.
An Acad Bras Cienc ; 96(3): e20230474, 2024.
Article En | MEDLINE | ID: mdl-38655921

The Pacific Oyster was introduced on Santa Catarina Island in 1987, experiencing processes of selection and genetic breeding since then. Such procedures may have led to the establishment of specific strains, given the saltier and warmer conditions of the Atlantic Ocean. This study employed microsatellite markers to compare allelic patterns of oysters cultivated in Santa Catarina, the USA, and Asia. Specific allelic patterns were revealed in the Santa Catarina samples, reflecting the time of selection/breeding of the oyster in this region. This result supports the effectiveness of the selection/breeding procedures and the demand for protection of this commercially important genetic resource.


Crassostrea , Genetic Variation , Microsatellite Repeats , Microsatellite Repeats/genetics , Animals , Crassostrea/genetics , Crassostrea/classification , Brazil , Genetic Variation/genetics , Breeding , Alleles
15.
Planta ; 259(6): 134, 2024 Apr 26.
Article En | MEDLINE | ID: mdl-38671234

MAIN CONCLUSION: Mfind is a tool to analyze the impact of microsatellite presence on DNA barcode specificity. We found a significant correlation between barcode entropy and microsatellite count in angiosperm. Genetic barcodes and microsatellites are some of the identification methods in taxonomy and biodiversity research. It is important to establish a relationship between microsatellite quantification and genetic information in barcodes. In order to clarify the association between the genetic information in barcodes (expressed as Shannon's Measure of Information, SMI) and microsatellites count, a total of 330,809 DNA barcodes from the BOLD database (Barcode of Life Data System) were analyzed. A parallel sliding-window algorithm was developed to compute the Shannon entropy of the barcodes, and this was compared with the quantification of microsatellites like (AT)n, (AC)n, and (AG)n. The microsatellite search method utilized an algorithm developed in the Java programming language, which systematically examined the genetic barcodes from an angiosperm database. For this purpose, a computational tool named Mfind was developed, and its search methodology is detailed. This comprehensive study revealed a broad overview of microsatellites within barcodes, unveiling an inverse correlation between the sumz of microsatellites count and barcodes information. The utilization of the Mfind tool demonstrated that the presence of microsatellites impacts the barcode information when considering entropy as a metric. This effect might be attributed to the concise length of DNA barcodes and the repetitive nature of microsatellites, resulting in a direct influence on the entropy of the barcodes.


Algorithms , DNA Barcoding, Taxonomic , Magnoliopsida , Microsatellite Repeats , Microsatellite Repeats/genetics , DNA Barcoding, Taxonomic/methods , Magnoliopsida/genetics , DNA, Plant/genetics
16.
Mol Biol Rep ; 51(1): 582, 2024 Apr 27.
Article En | MEDLINE | ID: mdl-38678168

BACKGROUND: Hybridization associated with polyploidy studies is rare in the tropics. The genus Zygopetalum (Orchidaceae) was investigated here as a case study of Neotropical plants. In the rocky highlands of the Ibitipoca State Park (ISP), southeast Brazil, individuals with intermediate colors and forms between the species Z. maculatum and Z. triste were commonly identified. METHODS AND RESULTS: Chromosomal analysis and DNA quantity showed a uniform population. Regardless of the aspects related to the color and shape of floral structures, all individuals showed 2n = 96 chromosomes and an average of 14.05 pg of DNA. Irregularities in meiosis associated with chromosome number and C value suggest the occurrence of polyploidy. The genetic distance estimated using ISSR molecular markers revealed the existence of genetic variability not related to morphological clusters. Morphometric measurements of the flower pieces revealed that Z. maculatum shows higher variation than Z. triste although lacking a defined circumscription. CONCLUSION: The observed variation can be explained by the polyploid and phenotypic plasticity resulting from the interaction of the genotypes with the heterogeneous environments observed in this habitat.


Genetic Variation , Orchidaceae , Phenotype , Polyploidy , Orchidaceae/genetics , Genetic Variation/genetics , Brazil , Chromosomes, Plant/genetics , Genotype , Flowers/genetics , Flowers/anatomy & histology , Microsatellite Repeats/genetics , Hybridization, Genetic/genetics
17.
Biochemistry ; 63(8): 969-983, 2024 Apr 16.
Article En | MEDLINE | ID: mdl-38623046

Fragile sites are unstable genomic regions that are prone to breakage during stressed DNA replication. Several common fragile sites (CFS) contain A+T-rich regions including perfect [AT/TA] microsatellite repeats that may collapse into hairpins when in single-stranded DNA (ssDNA) form and coincide with chromosomal hotspots for breakage and rearrangements. While many factors contribute to CFS instability, evidence exists for replication stalling within [AT/TA] microsatellite repeats. Currently, it is unknown how stress causes replication stalling within [AT/TA] microsatellite repeats. To investigate this, we utilized FRET to characterize the structures of [AT/TA]25 sequences and also reconstituted lagging strand replication to characterize the progression of pol δ holoenzymes through A+T-rich sequences. The results indicate that [AT/TA]25 sequences adopt hairpins that are unwound by the major ssDNA-binding complex, RPA, and the progression of pol δ holoenzymes through A+T-rich sequences saturated with RPA is dependent on the template sequence and dNTP concentration. Importantly, the effects of RPA on the replication of [AT/TA]25 sequences are dependent on dNTP concentration, whereas the effects of RPA on the replication of A+T-rich, nonstructure-forming sequences are independent of dNTP concentration. Collectively, these results reveal complexities in lagging strand replication and provide novel insights into how [AT/TA] microsatellite repeats contribute to genome instability.


DNA Polymerase III , DNA Replication , Humans , DNA Polymerase III/genetics , DNA Polymerase III/metabolism , DNA, Single-Stranded/genetics , Holoenzymes/genetics , Microsatellite Repeats , Nucleotides
18.
Front Immunol ; 15: 1354613, 2024.
Article En | MEDLINE | ID: mdl-38617840

Metastatic colon cancer remains an incurable disease, and it is difficult for existing treatments to achieve the desired clinical outcome, especially for colon cancer patients who have received first-line treatment. Although immune checkpoint inhibitors (ICIs) have demonstrated durable clinical efficacy in a variety of solid tumors, their response requires an inflammatory tumor microenvironment. However, microsatellite-stable (MSS) colon cancer, which accounts for the majority of colorectal cancers, is a cold tumor that does not respond well to ICIs. Combination regimens open the door to the utility of ICIs in cold tumors. Although combination therapies have shown their advantage even for MSS colon cancer, it remains unclear whether combination therapies show their advantage in patients with pretreated metastatic colon cancer. We report a patient who has achieved complete remission and good tolerance with sintilimab plus bevacizumab and platinum-based chemotherapy after postoperative recurrence. The patient had KRAS mutation and MSS-type colon cancer, and his PD-1+CD8+ and CD3-CD19-CD14+CD16-HLA-DR were both positive. He has achieved a progression-free survival of 43 months and is still being followed up at our center. The above results suggest that this therapeutic regimen is a promising treatment modality for the management of pretreated, MSS-type and KRAS-mutated metastatic colorectal cancer although its application to the general public still needs to be validated in clinical trials.


Antibodies, Monoclonal, Humanized , Colonic Neoplasms , Proto-Oncogene Proteins p21(ras) , Male , Humans , Bevacizumab/therapeutic use , Proto-Oncogene Proteins p21(ras)/genetics , Pathologic Complete Response , Colonic Neoplasms/drug therapy , Colonic Neoplasms/genetics , Platinum , Microsatellite Repeats , Tumor Microenvironment
19.
PLoS One ; 19(4): e0302273, 2024.
Article En | MEDLINE | ID: mdl-38625982

Cyphocharax magdalenae, a Colombian freshwater fish species, plays a vital role in nutrients distribution and serves as a significant food source for other fish species and local fishing communities. Considered a short-distance migratory species, C. magdalenae populations face substantial extinction risk due to human activities impacting their habitats. To address the lack of knowledge on genetic diversity and population structure, this study used next-generation sequencing technology to develop species-specific microsatellite loci and conducted a population genetics analysis of C. magdalenae in the middle and lower sections of the Cauca River, Colombia. Out of 30 pairs of microsatellite primers evaluated in 324 individuals, 14 loci were found to be polymorphic, at linkage equilibrium and, in at least one population, their genotypic frequencies were in Hardy-Weinberg equilibrium. Results showed high genetic diversity levels compared to other neotropical Characiformes, with inbreeding coefficients similar to those reported for phylogenetically related species. Moreover, C. magdalenae exhibits seasonal population structure (rainy-dry) consisting of two genetic stocks showing bottleneck signals and high effective population sizes. This information is essential for understanding the current species genetics and developing future management programs for this fishery resource.


Characiformes , Rivers , Animals , Humans , Colombia , Characiformes/genetics , Genetics, Population , Microsatellite Repeats/genetics , Genetic Loci , Genetic Variation
20.
Sheng Wu Gong Cheng Xue Bao ; 40(4): 1211-1224, 2024 Apr 25.
Article Zh | MEDLINE | ID: mdl-38658158

To study the genetic background of lily (Lilium spp.) germplasm resources, and accurately evaluate and select excellent germplasm for genetic improvement of lily, we analyzed the genetic background of 62 lily germplasm accessions from 11 provinces of China by using simple sequence repeat (SSR) molecular markers. The results showed that 15 out of 83 pairs of lily SSR primers were polymorphic. A total of 157 allelic loci were amplified, with the number of alleles per locus ranging from 5 to 19 and the average number of effective alleles per locus being 4.162 8. The average observed heterozygosity and expected heterozygosity were 0.228 2 and 0.694 1, respectively. The average polymorphic information content was 0.678 8. The average Nei's diversity index and Shannon's information index were 0.694 1 and 1.594 9, respectively, indicating that the tested lily germplasm had high genetic diversity. The 62 germplasm accessions were classified into 5 groups by the unweighted pair group method with arithmetic mean (UPGMA) and into 3 groups by the principal component analysis. The two analyses revealed a geographic correlation among different groups. The majority of lily germplasm accessions from the same source tended to cluster together. The population structure analysis classified the lily accessions into 4 populations and 1 mixed population. The above results provide a theoretical basis and genetic resources for the precise identification and breeding of lily germplasm resources.


Genetic Variation , Lilium , Microsatellite Repeats , Polymorphism, Genetic , Lilium/genetics , Lilium/classification , Microsatellite Repeats/genetics , China , Genetic Markers , Alleles , DNA, Plant/genetics
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