Molecular mechanism of temperature-dependent sex determination and differentiation in Chinese alligator revealed by developmental transcriptome profiling

The discovery in mammals that fetal testes are required in order to develop the male phenotype inspired research efforts to elucidate the mechanisms underlying gonadal sex determination and differentiation in vertebrates. A pioneer work in 1966 that demonstrated the influence of incubation temperature on sexual phenotype in some reptilian species triggered great interest in the environment’s role as a modulator of plasticity in sex determination. Several chelonian species have been used as animal models to test hypotheses concerning the mechanisms involved in temperature-dependent sex determination (TSD). This brief review intends to outline the history of scientific efforts that corroborate our current understanding of the state-of-the-art in TSD using chelonian species as a reference.

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Transcriptomic Analysis of the Anthocyanin Biosynthetic Pathway Reveals the Molecular Mechanism Associated with Purple Color Formation in Dendrobium Nestor

Life ◽

10.3390/life11020113 ◽

2021 ◽

Vol 11 (2) ◽

pp. 113

Author(s):

Xueqiang Cui ◽

Jieling Deng ◽

Changyan Huang ◽

Xuan Tang ◽

Xianmin Li ◽

...

Keyword(s):

Molecular Mechanism ◽

Developmental Stages ◽

Anthocyanin Biosynthesis ◽

Transcriptome Profiling ◽

Flower Color ◽

Flower Bud ◽

Color Formation ◽

Color Development ◽

Purple Coloration ◽

Purple Color

Dendrobium nestor is a famous orchid species in the Orchidaceae family. There is a diversity of flower colorations in the Dendrobium species, but knowledge of the genes involved and molecular mechanism underlying the flower color formation in D. nestor is less studied. Therefore, we performed transcriptome profiling using Illumina sequencing to facilitate thorough studies of the purple color formation in petal samples collected at three developmental stages, namely—flower bud stage (F), half bloom stage (H), and full bloom stage (B) in D. nestor. In addition, we identified key genes and their biosynthetic pathways as well as the transcription factors (TFs) associated with purple flower color formation. We found that the phenylpropanoid–flavonoid–anthocyanin biosynthesis genes such as phenylalanine ammonia lyase, chalcone synthase, anthocyanidin synthase, and UDP-flavonoid glucosyl transferase, were largely up-regulated in the H and B samples as compared to the F samples. This upregulation might partly account for the accumulation of anthocyanins, which confer the purple coloration in these samples. We further identified several differentially expressed genes related to phytohormones such as auxin, ethylene, cytokinins, salicylic acid, brassinosteroid, and abscisic acid, as well as TFs such as MYB and bHLH, which might play important roles in color formation in D. nestor flower. Sturdy upregulation of anthocyanin biosynthetic structural genes might be a potential regulatory mechanism in purple color formation in D. nestor flowers. Several TFs were predicted to regulate the anthocyanin genes through a K-mean clustering analysis. Our study provides valuable resource for future studies to expand our understanding of flower color development mechanisms in D. nestor.

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Variation in nesting patterns affecting nest temperatures in two populations of painted turtles (Chrysemys picta) with temperature-dependent sex determination

Behavioral Ecology and Sociobiology ◽

10.1007/s00265-002-0570-3 ◽

2003 ◽

Vol 53 (4) ◽

pp. 254-261 ◽

Cited By ~ 63

Author(s):

Carrie L. Morjan

Keyword(s):

Sex Determination ◽

Chrysemys Picta ◽

Temperature Dependent ◽

Painted Turtles ◽

Nesting Patterns ◽

Two Populations

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Transcriptome profiling analysis of muscle tissue reveals potential candidate genes affecting water holding capacity in Chinese Simmental beef cattle

Scientific Reports ◽

10.1038/s41598-021-91373-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Lili Du ◽

Tianpeng Chang ◽

Bingxing An ◽

Mang Liang ◽

Xinghai Duan ◽

...

Keyword(s):

Beef Cattle ◽

Candidate Genes ◽

Molecular Mechanism ◽

Meat Quality ◽

Relevant Literature ◽

Transcriptome Profiling ◽

Water Holding Capacity ◽

Potential Candidate ◽

Protein Protein Interaction ◽

Water Holding

AbstractWater holding capacity (WHC) is an important sensory attribute that greatly influences meat quality. However, the molecular mechanism that regulates the beef WHC remains to be elucidated. In this study, the longissimus dorsi (LD) muscles of 49 Chinese Simmental beef cattle were measured for meat quality traits and subjected to RNA sequencing. WHC had significant correlation with 35 kg water loss (r = − 0.99, p < 0.01) and IMF content (r = 0.31, p < 0.05), but not with SF (r = − 0.20, p = 0.18) and pH (r = 0.11, p = 0.44). Eight individuals with the highest WHC (H-WHC) and the lowest WHC (L-WHC) were selected for transcriptome analysis. A total of 865 genes were identified as differentially expressed genes (DEGs) between two groups, of which 633 genes were up-regulated and 232 genes were down-regulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment revealed that DEGs were significantly enriched in 15 GO terms and 96 pathways. Additionally, based on protein–protein interaction (PPI) network, animal QTL database (QTLdb), and relevant literature, the study not only confirmed seven genes (HSPA12A, HSPA13, PPARγ, MYL2, MYPN, TPI, and ATP2A1) influenced WHC in accordance with previous studies, but also identified ATP2B4, ACTN1, ITGAV, TGFBR1, THBS1, and TEK as the most promising novel candidate genes affecting the WHC. These findings could offer important insight for exploring the molecular mechanism underlying the WHC trait and facilitate the improvement of beef quality.

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Evolutionary transitions between mechanisms of sex determination in vertebrates

Biology Letters ◽

10.1098/rsbl.2010.1126 ◽

2011 ◽

Vol 7 (3) ◽

pp. 443-448 ◽

Cited By ~ 62

Author(s):

Alexander E. Quinn ◽

Stephen D. Sarre ◽

Tariq Ezaz ◽

Jennifer A. Marshall Graves ◽

Arthur Georges

Keyword(s):

Sex Determination ◽

Chromosome Pair ◽

Sex Chromosome ◽

Molecular Pathways ◽

Genetic Contribution ◽

Temperature Dependent ◽

Trait Evolution ◽

Evolutionary Transitions ◽

Dichotomous Outcome ◽

Threshold Trait

Sex in many organisms is a dichotomous phenotype—individuals are either male or female. The molecular pathways underlying sex determination are governed by the genetic contribution of parents to the zygote, the environment in which the zygote develops or interaction of the two, depending on the species. Systems in which multiple interacting influences or a continuously varying influence (such as temperature) determines a dichotomous outcome have at least one threshold. We show that when sex is viewed as a threshold trait, evolution in that threshold can permit novel transitions between genotypic and temperature-dependent sex determination (TSD) and remarkably, between male (XX/XY) and female (ZZ/ZW) heterogamety. Transitions are possible without substantive genotypic innovation of novel sex-determining mutations or transpositions, so that the master sex gene and sex chromosome pair can be retained in ZW–XY transitions. We also show that evolution in the threshold can explain all observed patterns in vertebrate TSD, when coupled with evolution in embryonic survivorship limits.

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