De novo transcriptomic analysis of Doum Palm (Hyphaene compressa) revealed an insight into its potential drought tolerance.

BACKGROUND: Doum palms (Hyphaene compressa) perform a crucial starring role in the lives of Kenya's arid and semi-arid people for empowerment and sustenance. Despite the crop's potential for economic gain, there is a lack of genetic resources and detailed information about its domestication at the molecular level. Given the doum palm's vast potential as a widely distributed plant in semi-arid and arid climates and a source of many applications, coupled with the current changing climate scenario, it is essential to understand the molecular processes that provide drought resistance to this plant. RESULTS: Assembly of the first transcriptome of doum palms subjected to water stress generated about 39.97 Gb of RNA-Seq data. The assembled transcriptome revealed 193,167 unigenes with an average length of 1655 bp, with 128,708 (66.63%) successfully annotated in seven public databases. Unigenes exhibited significant differentially expressed genes (DEGs) in well-watered and stressed-treated plants, with 45071 and 42457 accounting for up-regulated and down-regulated DEGs, respectively. GO term, KEGG, and KOG analysis showed that DEGs were functionally enriched cellular processes, metabolic processes, cellular and catalytic activity, metabolism, genetic information processing, signal transduction mechanisms, and posttranslational modification pathways. Transcription factors (TF), such as the MYB, WRKY, NAC family, FAR1, B3, bHLH, and bZIP, were the prominent TF families identified as doum palm DEGs encoding drought stress tolerance. CONCLUSIONS: This study provides a complete understanding of DEGs involved in drought stress at the transcriptome level in doum palms. This research is, therefore, the foundation for the characterization of potential genes, leading to a clear understanding of its drought stress responses and providing resources for improved genetic modification.

The Human Biting Culex pipiens Bioform molestus Detected in Several Areas in Southern Sweden.

Background: The mosquito species Culex pipiens is a known vector of several pathogens and occurs in two distinct bioforms, pipiens and molestus. The bioform molestus thrives in urban environments where there are below-ground habitats; it can mate in confined spaces and feed on mammals as well as birds. In contrast, the bioform pipiens is found above ground, is thought to require more space for mating, and mainly feeds on birds. The pipiens bioform is present in large parts of Sweden but the molestus bioform has previously only been found in major cities. Materials and Methods: People experiencing mosquito nuisance in southern Sweden submitted mosquito samples as part of a citizen science project, and these samples were analyzed to determine the geographical distribution of the molestus bioform of Cx. pipiens. Mosquito specimens were identified to the species level by DNA barcoding of the cytochrome C oxidase subunit I (COI) gene, and the bioforms were determined through the CQ11 microsatellite marker. Results:Culex pipiens f molestus was observed to be spread across large parts of Gothenburg as well as in the suburbs. This bioform was found both in urban and rural areas at several sites across southern Sweden. In one site, hybrids between the two bioforms were found. Conclusions: The detection of Cx. pipiens f molestus in several rural areas was surprising, indicating that it may be more widely spread than urban areas alone, where it has been previously reported.

Epidemiological Trends of Five Common Diarrhea-Associated Enteric Viruses Pre- and Post-Rotavirus Vaccine Introduction in Coastal Kenya.

Using real-time RT-PCR, we screened stool samples from children aged <5 years presenting with diarrhea and admitted to Kilifi County Hospital, coastal Kenya, pre- (2003 and 2013) and post-rotavirus vaccine introduction (2016 and 2019) for five viruses, namely rotavirus group A (RVA), norovirus GII, adenovirus, astrovirus and sapovirus. Of the 984 samples analyzed, at least one virus was detected in 401 (40.8%) patients. Post rotavirus vaccine introduction, the prevalence of RVA decreased (23.3% vs. 13.8%, p < 0.001) while that of norovirus GII increased (6.6% vs. 10.9%, p = 0.023). The prevalence of adenovirus, astrovirus and sapovirus remained statistically unchanged between the two periods: 9.9% vs. 14.2%, 2.4% vs. 3.2 %, 4.6% vs. 2.6%, (p = 0.053, 0.585 and 0.133), respectively. The median age of diarrhea cases was higher post vaccine introduction (12.5 months, interquartile range (IQR): 7.9-21 vs. 11.2 months pre-introduction, IQR: 6.8-16.5, p < 0.001). In this setting, RVA and adenovirus cases peaked in the dry months while norovirus GII and sapovirus peaked in the rainy season. Astrovirus did not display clear seasonality. In conclusion, following rotavirus vaccine introduction, we found a significant reduction in the prevalence of RVA in coastal Kenya but an increase in norovirus GII prevalence in hospitalized children.

Expression Levels of Odorant Receptor Genes in the Savanna Tsetse Fly, Glossina morsitans morsitans.

Tsetse flies (Glossina) are vectors of African trypanosomiasis. Olfaction plays a critical role in Glossina behavior, including larviposition, feeding, and reproduction. Odorant receptors (ORs) are important in insect chemoreception as they bind volatile odorants and transport them to olfactory receptor neurons to elicit behavioral response. To better understand Glossina chemoreception, we used quantitative polymerase chain reaction to examine the expression levels of ORs in female and male Glossina morsitans morsitans Wiedemann, 1850 (Diptera: Glossinidae) antennae and legs. Results showed that G. m. morsitans ORs code for a transmembrane domain and are involved in odorant binding. The ORs had homologs in Drosophila, mosquitoes, other Glossina species, and the reduced number of tsetse ORs could be linked to its restricted blood-feeding diet. The OR genes were more highly expressed in antennae than the legs with GmmOR33 and GmmOR45 transcript levels being high in the female and male antennae, respectively, whereas GmmOR26 and GmmOR34 levels were high in female and male G. m. morsitans legs, respectively. These findings identified sex- and tissue-specific G. m. morsitans ORs. The expression levels of OR genes in female and male G. m. morsitans could be conserved in function with the antenna being the main olfactory organ. Thus, this study provides a blueprint to explore the functional roles of tsetse ORs with the potential to identify molecular targets that can be used to control the vector based on disruption of its chemosensory system.

Phylogenetic Variants of Rickettsia africae, and Incidental Identification of "Candidatus Rickettsia Moyalensis" in Kenya.

BACKGROUND: Rickettsia africae, the etiological agent of African tick bite fever, is widely distributed in sub-Saharan Africa. Contrary to reports of its homogeneity, a localized study in Asembo, Kenya recently reported high genetic diversity. The present study aims to elucidate the extent of this heterogeneity by examining archived Rickettsia africae DNA samples collected from different eco-regions of Kenya. METHODS: To evaluate their phylogenetic relationships, archived genomic DNA obtained from 57 ticks a priori identified to contain R. africae by comparison to ompA, ompB and gltA genes was used to amplify five rickettsial genes i.e. gltA, ompA, ompB, 17kDa and sca4. The resulting amplicons were sequenced. Translated amino acid alignments were used to guide the nucleotide alignments. Single gene and concatenated alignments were used to infer phylogenetic relationships. RESULTS: Out of the 57 DNA samples, three were determined to be R. aeschlimanii and not R. africae. One sample turned out to be a novel rickettsiae and an interim name of "Candidatus Rickettsia moyalensis" is proposed. The bonafide R. africae formed two distinct clades. Clade I contained 9% of the samples and branched with the validated R. africae str ESF-5, while clade II (two samples) formed a distinct sub-lineage. CONCLUSIONS: This data supports the use of multiple genes for phylogenetic inferences. It is determined that, despite its recent emergence, the R. africae lineage is diverse. This data also provides evidence of a novel Rickettsia species, Candidatus Rickettsia moyalensis.