The distribution of a missense mutation in SDK1 gene across native Chinese breeds.

Sidekick cell adhesion molecule 1 (SDK1) gene belonging to the immunoglobulin superfamily (IgSF) is reported to be associated with disease resistance. A novel missense mutation (XM_015469413.1: c.2678 A > G: p. Asp893Gly) in bovine SDK1 gene was observed in the Bovine Genome Variation Database (BGVD). The purpose of the current study was to determine the allelic frequency distribution of XM_015469413.1: c.2678 A > G: p. Asp893Gly and analyze its association with disease resistance in native Chinese cattle. Here, we explored the allele frequency of the missense mutation (M_015469413.1: c.2678 A > G: p. Asp893Gly) in 542 individuals from 27 Chinese indigenous cattle breeds using PCR and DNA sequencing methods. The frequency of the mutant allele (G) gradually decreased from the southern cattle groups to the northern cattle groups, whereas the frequency of the wild-type allele A showed an opposite pattern, consistent with the distribution of indicine and taurine cattle in China. Thus, our results proved that the bovine SDK1 gene might be candidate genes associated with disease resistance in Chinese cattle.

CNV analysis of VAMP7 gene reveals variation associated with growth traits in Chinese cattle.

Copy number variant (CNV), a common genetic polymorphism, is closely related to the phenotypic variation traits of organisms. Vesicle-associated membrane protein 7 gene (VAMP7) codes a protein, which is a member of the SNARE proteins family and plays an important role in the process of intracellular vesicle transport. In this study, a total of four cattle breeds (Yunling cattle, Xianan cattle, Pinan cattle, Jiaxian red cattle) were used to investigate the copy numbers, and we found an association relationship between CNV of VAMP7 gene and growth traits of cattle by SPSS 20.0 software. The results showed that the CNV type of VAMP7 gene in four cattle breeds had the same distribution, Duplication type occupies a dominant position among the four varieties. In Yunling cattle, the Duplication type of VAMP7 is significantly related to the height at the hip cross (p < 0.05), Individuals with Duplication type commonly have less performance on growth and development, which indicates that the Duplication type of the VAMP7 gene may have a negative effect on cattle growth. Individuals with the other two CNV types may become the breeding direction of the VAMP7 gene. This study provided a new perspective and basic material for the molecular genetics of the CNV of the VAMP7 gene, and also promoted the breeding progress of Chinese local cattle.

Association between copy number variation of SERPINA3-1 gene and growth traits in Chinese cattle.

Serpin peptidase inhibitor, clade A (alpha-1 antiproteinase, antitrypsin), member 3 (SERPINA3) belongs to the serine protease inhibitor family A subtype, and contains 8 genes from SERPINA3-1 to SERPINA3-8. Although the regulatory effects of these 8 genes have been revealed one by one in recent years, the related effects of SERPINA3-1 gene on cattle growth is still unclear. This study used quantitative Real time PCR (qPCR) to detect the type of copy number variation (CNV) of SERPINA3-1 gene in a total of 542 Chinese cattle, and expression of SERPINA3-1 gene in different tissues of Qinchuan cattles (adult) on mRNA level. Then association analysis was conducted between the detection results and cattle growth traits. The results showed that the Duplication type in SERPINA3-1 gene performed better on the growth traits and the CNV was significantly correlated with multiple growth traits (p < 0.05). In addition, SERPINA3-1 gene has different expression conditions in different tissues, results showed that SERPINA3-1 gene has a low expression in muscle. In conclusion, we speculate that the SERPINA3-1 gene can be used as a molecular marker and the result of this study could be a basic material for candidate functional genes for beef cattle growth and development.

In order to detect the gene expression diversification of the SERPINA3-1 gene, blood samples were collected from five Chinese cattle breeds, we detected related signal and made an associated analyze with cattle growth traits. We determined the copy number variation distribution of the SERPINA3-1 gene in cattle populations and found that the SERPINA3-1 gene has a certain promoting effect on the growth and development of Chinese cattle. For example, Pinan cattle with Duplication type copy number have a better performance on growth traits. This study has enriched the candidate genes of Chinese cattle molecular breeding and provided basic data for Chinese cattle breeding.

DNA methylation status of SERPINA3 gene involved in mRNA expression in three cattle breeds.

DNA methylation could take part in the gene expression and acts an important role in muscle development. In this study, DNA methylation and expression in adipose and muscle tissues were examined at the same time to evaluate the extent of epigenetic modifications and gene expression on the differentially methylated region (DMR) in SERPINA3. Chain reaction of bisulfite sequencing polymerase (BSP) was used to compared difference among DNA methylation patterns. The result of quantitative real-time PCR (qPCR) analysis showed that there was an extensive expression of SERPINA3 gene in tissue and there was a significant difference existing in muscle and adipose between Jiaxian cattle and individual of other breeds with increasing hybridization (p < 0.05). The statistic analyses indicated that DNA methylation patterns had a significant influence to the level of mRNA in tissue of fat and muscle. This study may be an important reference for investigating development of muscle tissue in cattle, and may promote the process of cattle molecular breeding.

Distribution and association study of PLAG1 gene between copy number variation and Chinese cattle populations.

Copy number variation mainly refers to the copy number change of DNA fragments from 1 to 5 Mb. The deletion, duplication, inversion and ectopic of these fragments are collectively referred to as CNV. Numerous studies have shown that transfer factors play a vital role in regulating the growth and development of the body, for example the pleomorphic adenoma gene (PLAG). However, there is no study of CNV in PLAG1 gene. We qualified copy numbers within PLAG1 gene in 8 cattle breeds (Qinchuan, Qaidamu, Jinjiang, Guangfeng, Ji'an, Jiaxian, Pinan and Xianan cattle) by quantitative PCR, and explored their impacts on CNV of PLAG1 gene and phenotypic traits in Xianan cattle. We defined Deletion into CN = 0, Normal into CN = 1 and Duplication into CN = 2. The results showed that the individual with type of CN = 1 has a significant better effect on heart girth in JA cattle population (p < 0.01); the individual with type of CN = 1 and CN = 0 has a better effect on Rump length in JX cattle population (p < 0.05); the individual with type of CN = 0 has a better effect on cannon bone circumference in XN cattle population (p < 0.05). Association analysis showed that in JA cattle, the number of CN = 2 is great in JA cattle population, and the performance of CN = 2 in heart girth is better than CN = 1; in JX cattle, the rump length of CN = 2 is less than individual with CN = 0 and CN = 1; in XN cattle, individuals with CN = 0 have a better performance on cannon bone circumference than others. The results can provide a theoretical basis for molecular breeding of Chinese cattle, molecular mark-assist selection (MAS) of growth traits of Chinese cattle, and rapidly establish a Chinese cattle population with excellent genetic resources. Simple summaryWith the living standards rising, people's demand for beef is getting higher and higher, and there is a great significance to improve the growth performance of cattle. We measured body size data and detected copy number type of different cattle breeds (Xianan cattle, Ji'an cattle and Jiaxian cattle), and analyzed the correlation between the two object. We found that copy number variation of PLAG1 gene significantly affected some growth traits of XN cattle, JA cattle, and JX cattle. This may provide the basic material for molecular marker-assisted selection breeding of Chinese cattle breeds.

Two cSNPs sites in the fatty acid-binding protein 4 (FABP4) gene and their association analysis with body measurement data in five Chinese cattle breeds.

Single nucleotide polymorphisms (SNPs) include the transition and transversion of a single base. In this study, we found two cSNPs (rs110757796 and rs110652478) in the FABP4 (fatty acid-binding protein 4) gene and tested their population genetic parameters in five Chinese cattle breeds. FABP4 is a key marker molecule for lipid production. It plays a crucial role in the growth and development of animals. Thus, we also analyze the association between the two cSNPs of FABP4 gene and body measurement data of Chinese cattle. Our results were indicated that rs110757796 was significantly associated with the chest width in Chinese cattle groups (p < 0.05). In addition, we tested the spatiotemporal expression profile of the bovine FABP4 gene and effect of genetic variation on its expression. It was found that bovine FABP4 gene has tissue-differential expression. Then, the genetic variation located on the exon has a certain effect on the expression of FABP4 gene in bovine muscle. Overall, our results provide that FABP4 could as a candidate gene to improve the progress of cattle molecular breeding.

DGAT1 K232A polymorphism is associated with milk production traits in Chinese cattle.

The production traits of cattle, especially milk trait, are of great significance to human life. A quantitative trait loci (QTL) associated with milk fat content was detected in the centromeric region of cattle chromosome 14. This QTL harbors a strong candidate gene called DGAT1 responsible for the milk quality. A non-conservative substitution of lysine by alanine (K232A) was found in DGAT1 gene producing a strong effect on milk composition and yield. The lysine (K allele) is associated with increased milk fat content, while the decreased milk fat content is linked to the alanine (A allele) amino acid. To estimate the frequencies of the DGAT1 K232A polymorphism in Chinese cattle breeds, PCR and DNA sequencing methods were used to investigate the polymorphism of DGAT1 K232A in a total of 682 individuals, including 655 Chinese cattle and 27 Holstein cattle. The results demonstrated that the frequency of K allele gradually elevated from the northern group to the southern group of native Chinese cattle, whereas the frequency of A allele showed a contrary pattern, displaying a significant geographical difference across native Chinese cattle breeds. Our results confirm that the southern cattle group has higher milk fat content than that of the northern group.

The combination between NCSTN gene copy number variation and growth traits in Chinese cattle.

Copy number variation (CNV) has been used as an important source of phenotypic and genetic diversity in recent years. Nicastrin (NCSTN) gene is usually attached to human diseases such as Alzheimer's disease, and Acne inversa. However, there are no essays about the NCSTN gene combining with cattle breeds. In our study, we discovered different distributions of NCSTN gene copy number and associated it with phenotypic traits in four Chinese yellow cattle breeds (XN, PN, QC and YL). The result turned out that the CNV of the NCSTN gene was associated with several growth traits, such as cannon circumference, chest girth and rump length (p < 0.05). In general, we revealed the eminence over CNV of NCSTN gene and economic traits, suggesting that the CNV of the NCSTN gene can be considered to be a promising molecular breeding marker of Chinese beef cattle.

Ultrasensitive determination of highly polar trimethyl phosphate in environmental water by molecularly imprinted polymeric fiber headspace solid-phase microextraction.

A sensitive, accurate, and cost effective method for the quantification of trimethyl phosphate, which is highly polar and volatile, in environmental water is presented. Trimethyl phosphate was headspace solid-phase microextracted on a molecularly imprinted polymeric fiber, and then the fiber was thermally desorbed in the gas chromatograph injector, and the compound was determined. The trimethyl phosphate imprinted polymeric fiber was prepared by copolymerization in a fused silica capillary tube and obtained by removal of the wall of fused silica capillary tube. The monolithic fiber displayed good selectivity toward trimethyl phosphate among its structural analogues. It was thermally stable up to 320°C so that it can withstand the high temperature of the gas chromatograph injector for desorption. The factors influencing the performance of its headspace solid-phase microextraction were studied. Under the optimal conditions, the method for quantification of trimethyl phosphate in environmental water was well developed. It exhibited significant linearity, the lowest limit of quantification to date, and good recoveries. Using this method, trimethyl phosphate was detected in five out of seven environmental water samples at concentration levels from 0.28 to 1.22 µg/L, illustrating the heavy pollution of trimethyl phosphate in environmental water.

SETDB1 promotes progression through upregulation of SF3B4 expression and regulates the immunity in ovarian cancer.

BACKGROUND: Ovarian cancer (OC) is the most lethal gynecologic malignant tumour. The mechanism promoting OC initiation and progression remains unclear. SET domain bifurcated histone lysine methyltransferase 1(SETDB1) acts as an oncogene in a variety of tumours. This study aims to explore the role of SETDB1 in OC. METHODS: GEO, TCGA, CSIOVDB and CPTAC databases jointly analysed SETDB1 mRNA and protein expression. Effect of SETDB1 expression on the clinical prognosis of OC patients was analysed through online Kaplan‒Meier plotter and CSIOVDB database. Then, the effect of SETDB1 in OC cells progression and mobility was examined using MTT, EdU, colony formation and transwell assay. Additionally, Cistrome DB database was used to visualize the binding of SETDB1 protein and splicing factor 3b subunit 4 (SF3B4) promoter, and dual-luciferase reporter gene assay was performed to confirm the interaction. Finally, bioinformatics analysis was employed to reveal the relationship between SETDB1 and the microenvironment of OC. RESULTS: In the present study, we found that SETDB1 was obviously upregulated in OC and its overexpression predicted poor prognosis of OC patients. Then, we verified that SETDB1 promoted the progression and motility of OC cells in vitro. Knockdown of SETDB1 had the opposite effect. Further research showed that SETDB1 acted as a transcription factor to activate SF3B4 expression. SF3B4 knockdown impaired the effect of SETDB1 to promote the proliferative capacity and motility of OC cells. Finally, the results of bioinformatics analysis confirmed that SETDB1 regulated the immune microenvironment of ovarian cancer. CONCLUSION: SETDB1 promoted ovarian cancer progression by upregulating the expression of SF3B4 and inhibiting the tumour immunity. SETDB1 may be a promising prognostic and therapeutic marker for OC.

Single-cell RNA sequencing in skeletal muscle developmental biology.

Skeletal muscle is the most extensive tissue in mammals, and they perform several functions; it is derived from paraxial mesodermal somites and undergoes hyperplasia and hypertrophy to form multinucleated, contractile, and functional muscle fibers. Skeletal muscle is a complex heterogeneous tissue composed of various cell types that establish communication strategies to exchange biological information; therefore, characterizing the cellular heterogeneity and transcriptional signatures of skeletal muscle is central to understanding its ontogeny's details. Studies of skeletal myogenesis have focused primarily on myogenic cells' proliferation, differentiation, migration, and fusion and ignored the intricate network of cells with specific biological functions. The rapid development of single-cell sequencing technology has recently enabled the exploration of skeletal muscle cell types and molecular events during development. This review summarizes the progress in single-cell RNA sequencing and its applications in skeletal myogenesis, which will provide insights into skeletal muscle pathophysiology.

A path planning method using modified harris hawks optimization algorithm for mobile robots.

Path planning is a critical technology that could help mobile robots accomplish their tasks quickly. However, some path planning algorithms tend to fall into local optimum in complex environments. A path planning method using a modified Harris hawks optimization (MHHO) algorithm is proposed to address the problem and improve the path quality. The proposed method improves the performance of the algorithm through multiple strategies. A linear path strategy is employed in path planning, which could straighten the corner segments of the path, making the obtained path smooth and the path distance short. Then, to avoid getting into the local optimum, a local search update strategy is applied to the HHO algorithm. In addition, a nonlinear control strategy is also used to improve the convergence accuracy and convergence speed. The performance of the MHHO method was evaluated through multiple experiments in different environments. Experimental results show that the proposed algorithm is more efficient in path length and speed of convergence than the ant colony optimization (ACO) algorithm, improved sparrow search algorithm (ISSA), and HHO algorithms.

Indoor high-precision visible light positioning system using Jaya algorithm.

Several indoor positioning systems that utilize visible light communication (VLC) have recently been developed. Due to the simple implementation and high precision, most of these systems are dependent on received signal strength (RSS). The position of the receiver can be estimated according to the positioning principle of the RSS. To improve positioning precision, an indoor three-dimensional (3D) visible light positioning (VLP) system with the Jaya algorithm is proposed. In contrast to other positioning algorithms, the Jaya algorithm has a simple structure with only one phase and achieves high accuracy without controlling the parameter settings. The simulation results show that an average error of 1.06 cm is achieved using the Jaya algorithm in 3D indoor positioning. The average errors of 3D positioning using the Harris Hawks optimization algorithm (HHO), ant colony algorithm with an area-based optimization model (ACO-ABOM), and modified artificial fish swam algorithm (MAFSA) are 2.21 cm, 1.86 cm and 1.56 cm, respectively. Furthermore, simulation experiments are performed in motion scenes, where a high-precision positioning error of 0.84 cm is achieved. The proposed algorithm is an efficient method for indoor localization and outperforms other indoor positioning algorithms.

Transcriptional and open chromatin analysis of bovine skeletal muscle development by single-cell sequencing.

Skeletal muscle is a complex heterogeneous tissue and characterizing its cellular heterogeneity and transcriptional and epigenetic signatures are important for understanding the details of its ontogeny. In our study, we applied scRNA-seq and scATAC-seq to investigate the cell types, molecular features, transcriptional and epigenetic regulation, and patterns of developing bovine skeletal muscle from gestational, lactational and adult stages. Detailed molecular analyses were used to dissect cellular heterogeneity, and we deduced the differentiation trajectory of myogenic cells and uncovered their dynamic gene expression profiles. SCENIC analysis was performed to demonstrate key regulons during cell fate decisions. We explored the future expression states of these heterogeneous cells by RNA velocity analysis and found extensive networks of intercellular communication using the toolkit CellChat. Moreover, the transcriptomic and chromatin accessibility modalities were confirmed to be highly concordant, and integrative analysis of chromatin accessibility and gene expression revealed key transcriptional regulators acting during myogenesis. In bovine skeletal muscle, by scRNA-seq and scATAC-seq analysis, different cell types such as adipocytes, endothelial cells, fibroblasts, lymphocytes, monocytes, pericyte cells and eight skeletal myogenic subpopulations were identified at the three developmental stages. The pseudotime trajectory exhibited a distinct sequential ordering for these myogenic subpopulations and eight distinct gene clusters were observed according to their expression pattern. Moreover, specifically expressed TFs (such as MSC, MYF5, MYOD1, FOXP3, ESRRA, BACH1, SIX2 and ATF4) associated with muscle development were predicted, and likely future transcriptional states of individual cells and the developmental dynamics of differentiation among neighbouring cells were predicted. CellChat analysis on the scRNA-seq data set then classified many ligand-receptor pairs among these cell clusters, which were further categorized into significant signalling pathways, including BMP, IGF, WNT, MSTN, ANGPTL, TGFB, TNF, VEGF and FGF. Finally, scRNA-seq and scATAC-seq results were successfully integrated to reveal a series of specifically expressed TFs that are likely to be candidates for the promotion of cell fate transition during bovine skeletal muscle development. Overall, our results outline a single-cell dynamic chromatin/transcriptional landscape for normal bovine skeletal muscle development; these provide an important resource for understanding the structure and function of mammalian skeletal muscle, which will promote research into its biology.

Effect of copy number variation of PLA2G2A gene to growth traits in Chinese cattle.

SIMPLE SUMMARY: As a member of genetic polymorphism, copy number variation has been a commonly used method in the world for investigating effect of genetic polymorphism on gene expression. Effect of genetic polymorphism made on livestock development has been more and more important in beef cattle molecular breeding. The characteristics of Chinese cattle are excellent meat quality, tolerant to rough feeding, good environmental adaptability and so on. But there are some obvious weaknesses still exist in the process of cattle growth and development, such as weak hindquarters and growth slowly. To improve the growth performance and market competitiveness of Chinese cattle, a lot of studies have been made about finding and investigating effective molecular marker. In this study, Q-PCR and data association analysis were used for PLA2G2A gene copy number variation detection and related effect analysis in Chinese cattle. Results showed that PLA2G2A gene has a significant effect on two breeds of Chinese cattle on growth traits, which could be a basic materials and effective information of cattle molecular markers breeding. PLA2G2A, member of secreted phospholipases A2 (sPLA2) in superfamily of phospholipase A2, could catalyze the process of glycerophospholipids hydrolysis from position of sn-2 acyl with the release of free fatty acids and lysophospholipids. Researches about PLA2G2A gene are mostly focus on disease, including tumors and diabetes, the number of study occurred on animal breeding is weak. In this study, blood samples were collected from five breeds of Chinese cattle (Qingchuan cattle, Xianan cattle, Yunling cattle, Pinan cattle and Guyuan cattle) for PLA2G2A gene CNV type detection. SPSS 20.0 software and method of ANOVA were used to analyzed the association between types of CNV and growth traits. Results reveal that the distribution of different copy number types in different cattle breeds is different. In QC, XN and GY cattle, the frequencies of Deletion and Duplication are about 40%; in YL cattle, the frequency of Deletion type exceeds 60%; in PN cattle, the frequency of Duplication is closed to 80%. Association analysis indicate that CNV of PLA2G2A gene showed a positive effect in cattle growth: in QC cattle, Chest depth with Normal type copy number possess a increased trend (P < 0.05); individuals with Deletion type copy number have better performance on Height at sacrum, Heart girth and Body height in GY cattle (P < 0.05). The functional role and molecular mechanism of PLA2G2A gene in animal growth and development are still unclear, and it is necessary for processing a further research. This research aims to provide basic materials for molecular breeding of Chinese cattle.

A novel missense mutation within KRT75 gene strongly affects heat stress in Chinese cattle.

The KRT75 gene (Keratin 75) is a member of the type II epithelial α-keratin gene family which plays a key role in hair and nail formation. And the coat conformation affects heat tolarence in mammals. Therefore, the aim of this study was to identify novel single nucleotide polymorphisms (SNPs) of the KRT75 gene and further evaluate its relation to heat stress in Chinese cattle. A missense mutation (NC_037332.1: g.1052 T > C) of the bovine KRT75 was identified using the Bovine Genome Variation Database (BGVD). The g.1052 T > C variant was then genotyped in 519 individuals of 22 cattle breeds. Further analyses showed that the frequency of T allele in Chinese indigenous cattle breeds gradually diminished from northern groups to southern groups, whereas the frequency of C allele displayed a contrary patternl. Simultaneously, the frequency of the CC and CT genotype for southern groups was much greater than that of the TT genotype. Additionally, association analysis showed the genotypes were remarkably associated with mean annual temperature (T), relative humidity (RH) and temperature humidity index (THI) (P < 0.01). Our results demonstrated that the KRT75 gene might be a candidate gene associated with the heat stress in Chinese cattle.

Genetic effects of MOGAT1 gene SNP in growth traits of Chinese cattle.

Single nucleotide polymorphism (SNP) has recently become one of the ideal genetic markers. SNP refers to the DNA sequence polymorphism caused by double nucleotide variation in the genome, including the conversion or transversion of segmented bases. The synthesis and metabolism of triglycerides are related to the changes of energy in the body of livestock, which in turn affects their growth and development. Studies have shown that MOGAT1 gene plays a role in the route of triglyceride synthesis. PCR-RFLP and agarose gel electrophoresis technology were used to type the SNP site of MOGAT1 gene at g.25940T > C in this study. Association analysis between typing results and growth trait data was detected by SPSS 20.0 software. Results show that MOGAT1 gene was in a low level of heterozygosity in Xianan, Qinchuan and Pinan cattle population (0 < PIC < 0.25), and in middle level of heterozygosity in YL cattle population(0.25 < PIC < 0.5). And genotype 'AA' was dominant gene in Chinese cattle population. In QC and XN cattle, genotype of GG possess advantage on Body weight (P < 0.05); in YL cattle, individuals with genotype of homozygous mutation decreased significantly on Chest depth (P < 0.05). The purpose of this research is to provide theoretical materials for molecular breeding of yellow cattle and to promote the process of improving the growth traits of Chinese local yellow cattle.

The Association of the Copy Number Variation of the MLLT10 Gene with Growth Traits of Chinese Cattle.

Copy number variation is a part of genomic structural variation and has caused widespread concern. According to the results of high-throughput screening of the MLLT10 gene, we found that the copy number variation region of the MLLT10 gene was correlated with bovine growth traits. We aimed to detect the MLLT10 gene copy number variation and provide materials for the Chinese yellow cattle breed. In this study, the SPSS software was used to analyze the correlation among the copy number type of six different cattle breeds (i.e., Qinchuan, Xianan, Jiaxian, Yanbian, Sinan, Yunling) and the corresponding growth traits. The results showed the following: In Qinchuan cattle, the copy number duplication type was greater than the deletion and normal types; in Xianan cattle, the copy number duplication and normal types were less as compared with the deletion type; and in Yunling cattle, the frequency of the duplication type was dominant among the three types of copy number variants. The correlation analysis result showed that there is a significant correlation between the copy number variation (CNV) of the MLLT10 gene and the growth traits of three cattle breeds. Furthermore, correlation analysis showed that MLLT10 CNV had positive effects on growth traits such as hip width, rump length, hucklebone width, and cannon bone circumference (p < 0.05). This study provides a basis for the molecular-assisted marker breeding of cattle and contributes to the breeding of cattle.

Differential Expression of ACTL8 Gene and Association Study of Its Variations with Growth Traits in Chinese Cattle.

Mutations are heritable changes at the base level of genomic DNA. Furthermore, mutations lead to genetic polymorphisms and may alter animal growth phenotypes. Our previous study found that mutations in the bovine Actin-like protein 8 (ACTL8) gene may be involved in muscle growth and development. This study explored several mutations of the ACTL8 gene and their influence on body size in Chinese beef cattle, as well as tested the tissue expression profile of the ACTL8 gene in Qinchuan cattle at different ages. Five single nucleotide polymorphisms (SNPs) (including one synonymous mutation (c.2135552895G > A)) and two insertion/deletion polymorphisms (indels) were identified in the ACTL8 gene from 1138 cattle by DNA-seq, RFLP and other methods. Then, the expression profile of the ACTL8 gene in Qinchuan cattle showed that it was expressed in heart, spleen, lung, liver, muscle, and fat tissues. Moreover, the expression level of ACTL8 was increased with cattle growth (p < 0.01). The ACTL8 mRNA expression level in kidney and muscle tissues was the highest in the calves, while lowest in the fetal stage. Overall, we showed that the mutations could act as markers in beef molecular breeding and selection of the growth traits of cattle.

Four Novel SNPs of MYO1A Gene Associated with Heat-Tolerance in Chinese Cattle.

Based on the previous GWAS research related to bovine heat tolerance trait, this study aimed to explore the effect of myosin-1a (MYO1A) gene on bovine heat tolerance trait, and find the molecular markers related to the heat tolerance of Chinese cattle. In our study, four novel candidate SNPs highly conserved in B. indicus breeds but barely existed in B. taurus were identified in MYO1A gene according to Bovine Genome Variation Database and Selective Signatures (BGVD). PCR and DNA sequencing were used to genotype 1072 individuals including 34 Chinese indigenous cattle breeds as well as Angus and Indian zebu. Two synonymous mutations (rs208210464 and rs110123931), one missense mutation (rs209999142; Phe172Ser), and one intron mutation (rs135771836) were detected. The frequencies of mutant alleles of the four SNPs gradually increased from northern groups to southern groups of Chinese cattle, which was consistent with the distribution of various climatic conditions of China. Additionally, four SNPs were significantly associated with four climatic conditions including annual mean temperature (T), relative humidity (H), temperature-humidity index (THI), and average annual sunshine hours (100-cloudiness) (SR). Among these, rs209999142 and Hap 1/1 had better performance than others. Our results suggested that rs209999142 was associated with heat-tolerance trait and rs208210464, rs110123931, and rs135771836 showed high phenotypic effect on heat-tolerance trait because of the strong linkage with rs209999142. These SNPs could be used as candidates for marker-assisted selection (MAS) in cattle breeding.