Expression Profile of Chicken Sex Chromosome Gene < b > < i > BTF3 < /i > < /b > is Linked to Gonadal Phenotype

In birds, the female is heterogametic (ZW) and the male homogametic (ZZ). The small W chromosome comprises only 28 protein coding genes (homologues to Z chromosome counterparts) and a number of repeat regions. Here, we report our analysis of one of these genes,BTF3 (basic transcription factor 3), which exhibits differential expression during gonadogenesis. We measured RNA levels of both Z and W homologues and BTF3 protein levels in male and female gonads during development of the chicken embryo. In addition,BTF3 RNA and protein levels were compared in female gonads (ovary) and in female gonads following treatment to induce sex reversal (testis). CombinedBTF3 RNA levels were higher in female gonads than male gonads, whileBTF3-Z was expressed at similar levels in males and females. Surprisingly, BTF3 protein levels were higher in male gonads than female gonads at embryonic day 6 (E6), suggesting translational rather than transcriptional regulation. BTF3 protein was expressed in both somatic and germ cells and was restricted to the medulla of the developing ovary in females and the sex cords of the developing testis in males. In addition, in gonadal sex-reversed females, RNA and protein levels ofBTF3 were similar to those normally found in male gonads, suggesting thatBTF3 expression correlated with the gonadal phenotype.Sex Dev 2019;13:212-220

Source: Sexual Development - March 10, 2020 Category: Biology Source Type: research