Comparison of 5′ upstream regions of chicken and quail aromatase genes

Abstract

Aromatase (EC 1.14.14.1.) is a key enzyme of feminizing hormone biosynthesis and catalyzes the conversion of androgens to estrogens. In birds, sex-steroid hormones, especially estrogens, play a critical role in the development of the gonadal glands and the aromatase is one of the most important factors in sex determination. Herein, we cloned the 5′ upstream regions of chicken and quail aromatase genes and determined these sequences, which showed high homology between chicken and quail. Moreover, the transcription initiation site of the chicken aromatase gene in early development was determined by the 5′-RACE method. The findings showed that the transcription of the chicken aromatase gene starts from a more upstream site than previously reported.