Chromosome-level analysis of the Mauremys mutica genome reveals adaptation of temperature-dependent sex-associated genes

Knowledge of the sex determination system and sex-associated genes has important implications in physiology, ecology and evolution, but the mechanisms underlying sexual determination systems in turtles has not been fully elucidated, due to their remarkable variability and a lack of reference genomes in some species. In this report, we describe the first genome assembled at the chromosome scale for Mauremys mutica using Illumina and high-throughput chromatin conformation capture (Hi-C) technology. A total of 280.42 Gb of clean data were generated using the Pacific Biosciences platforms, which represented approximately 119× coverage of the Mauremys mutica genome. The assembly comprised 2.23 Gb with a contig N50 of 8.53 Mb and scaffold N50 of 141.98 Mb. Genome Hi-C scaffolding resulted in 26 pseudochromosomes containing 99.98% of the total assembly. Genome annotation predicted 24,751 protein-coding genes, and 97.23% of them were annotated. Comparative genomics analysis indicated that the lizard-snake-tuatara clade diverged from the bird-crocodilian-turtle clade at approximately 283.1-320.5 Mya. Additionally, positive selection of genes and gene families related to calcium signaling, neuroactive ligand-receptor interaction, and expansion of the hormone signaling pathway were identified, implicating their roles of sex regulation inMauremys mutica. High-quality genome assembly may provide a valuable genomic resource for further research investigating gene-environment interactions in Mauremys mutica.

Identification and Functional Analysis of the Sex-Determiner Transformer-2 Homologue in the Freshwater Pearl Mussel, Hyriopsis cumingii

Transformer-2 (Tra-2) is an upstream regulatory element of the sex regulation mechanism in insects and plays a critical role in sex formation. To understand the role of tra-2 in Hyriopsis cumingii, the full-length Hctra-2 (1867 bp) was obtained from the gonads, and sequence alignment with other species showed that HCTRA-2 protein had a highly conserved RRM domain. Phylogenetic analysis showed that the HCTRA-2 protein was a close relative to of the mollusks TRA-2 protein. The qRT-PCR of tissue-specific expression pattern showed that the Hctra-2 was abundant in gonads, and the expression in testes was higher than that in ovaries (p < 0.01). It suggests that Hctra-2 may play a potential regulatory role in gonadal development of H. cumingii. In the early gonadal development, the Hctra-2 expression was the highest on the third day after fertilization and increased slightly from 4 months to 5 months, which may be related to the embryonic sex determination and early gonadal development. In situ hybridization showed that Hctra-2 mRNA signals were present in both male and female gonads. After silencing Hctra-2 by RNAi, the expression levels of Hcfem-1b and Hcdmrt were changed. It is speculated that there may be a certain relationship between them, which plays an important role in the sex regulation of H. cumingii. Our research will help to deepen our understanding of the shellfish sex determination mechanisms.

Role of HOXC10 in Cancer

The HOXC10 gene, a member of the HOX genes family, plays crucial roles in mammalian physiological processes, such as limb morphological development, limb regeneration, and lumbar motor neuron differentiation. HOXC10 is also associated with angiogenesis, fat metabolism, and sex regulation. Additional evidence suggests that HOXC10 dysregulation is closely associated with various tumors. HOXC10 is an important transcription factor that can activate several oncogenic pathways by regulating various target molecules such as ERK, AKT, p65, and epithelial mesenchymal transition-related genes. HOXC10 also induces drug resistance in cancers by promoting the DNA repair pathway. In this review, we summarize HOXC10 gene structure and expression as well as the role of HOXC10 in different human cancer processes. This review will provide insight into the status of HOXC10 research and help identify novel targets for cancer therapy.

Female Developmental Environment Delays Development of Male Honeybee (Apis Mellifera)

Background Nutrition and cell size play an important role in the determination of caste differentiation in queen-worker of honeybee (Apis mellifera), whereas the haploid genome dominates the differentiation of drones. However, the effects of female developmental environment on the development of males remain unclear. In this study, young drone larvae were transferred into worker cells (WCs) or remained in drone cells (DCs) to rear drones. The parts of drone larvae were also grafted into queen cells (QCs) for 48 h and then transplanted into drone cells until emerging. Morphological indexes and reproductive organs of these three types of newly emerged drones were measured. Newly emerged drones and 3 d drone larvae from WCs, DCs and QCs were sequenced by RNA sequencing (RNA-Seq). Results Morphological results showed that newly emerged DC drones had bigger body sizes and more well-developed reproductive tissues than WC and QC drones, whereas the reproductive tissues of QC drones were relatively better than those of WC drones. Gene expression results showed a more clear difference among three groups. At the larval stage, there were 889, 1761 and 1927 significantly differentially expressed genes (DEGs) in WC/DC, QC/DC and WC/QC comparisons, respectively. The number of DEGs decreased in adult drones of these three comparisons [678 (WC/DC), 338 (QC/DC) and 518 (WC/QC)]. A high number of DEGs were involved in sex regulation, growth, olfaction, vision, mammalian target of rapamycin (mTOR), Wnt signaling pathways, etc. Weighted gene co-expression network analysis (WCGNA) showed that WC and DC larvae were closer than QC larvae, whereas QC and WC drones were closer than DC drones. These results revealed that DC drones had better development in the body and reproductive system than QC and WC drones. Conclusion This study demonstrated that the developmental environment of honeybee females including the larval diet and cell size delayed male development. Naturally, honeybee colony ovigerous workers in queen-less colonies or non-mated queens produce a large number of dysplasia drones which are not well-developed. Therefore, this study serves as a model for understanding the regulation of sexual differentiation in social insects by environmental factors.

Comparison of the bacterial abundance and diversity in the Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) between both sexes

Background. Insects harbor a myriad of microorganisms, many of which can affect the sex ratio and manipulate the reproduction of the host. Leptocybe invasa is an invasive pest that causes serious damage to eucalyptus plantations, and both female-biased sex ratios and thelytokous parthenogenesis in L. invasa contribute to the rapid invasion and fast growth of the population. However, the interior bacterial composition and abundance of L. invasa and the differences between both sexes remain unclear. Results. The Illumina MiSeq platform was used to compare the composition of the bacterial community in adult females and males by sequencing with variation in the V3-V4 region of the 16S ribosomal DNA gene. The results showed that 1320 operational taxonomic units (OTUs) were obtained in total. These OTUs were annotated into 24 phyla, 71 classes, 130 orders, 245 families and 501 genera. At the genus level, the dominant bacteria in females and males was Rickettsia and Rhizobium, respectively. Conclusion. The bacteria living in L. invasa adult females and males had high diversity. There were differences in the bacterial community in L. invasa between both sexes, and the bacterial diversity in male adults was more abundant than that in female adults. This study presents a comprehensive comparison of bacterial communities living in L. invasa between sexes, which plays a significant role in reproductive strategy, sex regulation and the invasive mechanism of L. invasa and provides a basis for follow-up studies on the coevolution and interaction between L. invasa and its predominant bacteria.

Comparison of the bacterial abundance and diversity in the Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) between both sexes

Background. Insects harbor a myriad of microorganisms, many of which can affect the sex ratio and manipulate the reproduction of the host. Leptocybe invasa is an invasive pest that causes serious damage to eucalyptus plantations, and both female-biased sex ratios and thelytokous parthenogenesis in L. invasa contribute to the rapid invasion and fast growth of the population. However, the interior bacterial composition and abundance of L. invasa and the differences between both sexes remain unclear. Results. The Illumina MiSeq platform was used to compare the composition of the bacterial community in adult females and males by sequencing with variation in the V3-V4 region of the 16S ribosomal DNA gene. The results showed that 1320 operational taxonomic units (OTUs) were obtained in total. These OTUs were annotated into 24 phyla, 71 classes, 130 orders, 245 families and 501 genera. At the genus level, the dominant bacteria in females and males was Rickettsia and Rhizobium, respectively. Conclusion. The bacteria living in L. invasa adult females and males had high diversity. There were differences in the bacterial community in L. invasa between both sexes, and the bacterial diversity in male adults was more abundant than that in female adults. This study presents a comprehensive comparison of bacterial communities living in L. invasa between sexes, which plays a significant role in reproductive strategy, sex regulation and the invasive mechanism of L. invasa and provides a basis for follow-up studies on the coevolution and interaction between L. invasa and its predominant bacteria.

Sex and the Shari'a: Defining Gender Norms and Sexual Deviancy in Shi'i Islam

39 Fordham International Law Journal 25 (2015)This paper demonstrates that modern authoritative jurists working within the Shi'i tradition have developed their rules respecting sex regulation to serve three primary commitments. The first of these is that there is an intense and near debilitating desire on the part of human beings generally, though mostly men, for a great deal of sex. This desire must be satisfied, but it also must be tightly controlled. This is because of the second commitment, which is that excessive licentiousness is a form of secular distraction from a believer's central obligation to worship God. Finally, and perhaps the most interesting, is the commitment to maintain and uphold gender differentiation in order to ensure the preservation of traditional gender roles within a gendered hierarchy firmly established in the marital contract. That is, there must be clear delineations between men, on the one hand, and women, on the other, if hierarchies relating to the respective roles of husbands and wives are to be maintained. Having described the commitments, the paper sets out some of the key implications that result from them. These include fierce intolerance of nonmarital sex, which is presumed to distract the believer from the worship of God, and an even fiercer intolerance of homosexuality, which challenges the strict gender norms established in marital contracts. Interestingly, however, other consequences of Shi'i Islam's commitments are relative tolerance of sex change operations, and acceptance of at least some forms of sexual gratification with child wives. The conclusion offers brief remarks on the relationship of this normative framework to actual law and social practice in contemporary Shi'i societies.