巢湖鸭与樱桃谷鸭杂交羽色分离及相关基因表达研究

Expression analysis on genes corresponding to feather color regulation and separation in the hybridized F_1 group and F_2group(Cherry Valley duck ♂ with Chaohu duck ♀)

羽色作为鸭重要的包装性状之一,对其经济效益产生重要影响。为探讨鸭羽色遗传规律,试验记录巢湖鸭(♀)和樱桃谷鸭(♂)及其杂交F_1代、F_1代自交产生的F_2代羽色分离情况,并采用QRT-PCR分析小眼相关转录因子基因(MITF)、酪氨酸酶基因(TYR)、显色白毛调控基因(KIT)在不同生长阶段的相对表达量。结果表明:F_1和F_2代出雏羽色可分为黑白羽、灰羽和黄羽,4周龄后仅观察到黑白羽和麻羽(灰羽和黄羽脱换而成)。F_2代黑白羽鸭和麻羽鸭为9∶7(χ2=0.01)。F_1代和F_2代麻羽鸭中,TYR、KIT和MITF基因表达变化趋于一致,第4周的表达量达到高峰,且显著高于巢湖鸭和樱桃谷鸭。F_1和F_2代黑白羽鸭中,TYR、MITF基因表达量在各群体中差异不显著,KIT基因在F_1和F_2代黑白羽鸭中表达量显著高于同期巢湖鸭和樱桃谷鸭。根据F_2代羽色分离比例和表达差异,推测多对羽色基因间存在互补效应。

Feather color, economically connected character, was regarded as an important quality trait in duck. In this experiment, feather color was recorded among groups of Chaohu duck （ ♀ ）, Cherry Valley duck （ ♂ ） and their F1 gener- ation, the F2 generation from self-crossed F1 generation. The relative mRNA expression level of TYR, MITF and KIT, which were considered as major genes that control feather color formation, was quantified by real-time PCR. The duck- lings before 2 wk can be divided into black-white plumage, gray plumage and yellow plumage in F1 and F2 groups. After 4 wk, only black-white and partridge were observed in F1 and F2 groups with a ratio of 9 ： 7 （X2=0.01） in F2 group. The expression level of TYR, MITF and KIT showed similar trend in partridge duck from F1 and F2 groups and reached their highest level at 4 wk and significantly higher than that of Chaohu duck and Cherry Valley duck （P〈0.05）. The expres- sion level of TYR and MITE exhibited no difference in black-white feathered ducks from F1 and Fz groups, while the ex- pr.ession level of KIT was higher as compared to Chaohu duck and Cherry Valley duck （P〈0.05） during the same devel- oping period. Feather color was controlled by several allelic genes and non-allelic dominant genes at the same time. We suppose that feather color controlled genes showed complementary effect according to the separation ratio in F2 generation and gene expression trends.