不同基因型肉鸡肠道CAT1和CAT4 mRNA表达的发育性变化

Ontogenetic Expression of CAT1 and CAT4 mRNA in Intestine of Broiler

选用遗传背景相同的1 d父母代雄性Arbor Acre（AA）和父母代雄性岭南黄肉雏鸡各160羽,采用相对定量RT-PCR方法,以AA肉鸡和岭南黄鸡十二指肠、空肠和回肠样品为模板,研究不同基因型肉鸡肠道CAT1和CAT4mRNA表达的发育性变化。结果显示：十二指肠和空肠CAT1和CAT4mRNA表达的发育性变化与回肠有着较大的差异;岭南黄肉鸡十二指肠和空肠CAT1和CAT4 mRNA表达的发育性变化与AA肉鸡分别有显著差别;岭南黄肉鸡十二指肠和空肠CAT1 mRNA表达从2~58d逐渐降低,AA肉鸡除在44d有所降低,在其他时间点的表达丰度基本一致;岭南黄肉鸡十二指肠和空肠CAT4 mRNA从2~44d有降低的趋势,58d有所回升,AA肉鸡在58d的丰度最低,其他时间点的表达丰度基本一致;岭南黄肉鸡回肠CAT1 mRNA的表达丰度在2~44d呈逐渐降低的趋势,58和44d接近,而AA肉鸡则在58d达到最高,其他时间点接近;2~44d岭南黄肉鸡回肠中CAT4 mRNA表达的发育性变化与AA肉鸡一致,但58d出现差异,AA肉鸡降到最低而岭南黄肉鸡显著上升。以上结果说明：十二指肠与空肠中CAT1和CAT4 mRNA表达的发育性变化与回肠有着较大的差异,这表明肠道近端和远端在碱性氨基酸吸收的功能上可能有所差异;不同基因型肉鸡十二指肠、空肠和回肠CAT1和CAT4 mRNA表达的发育模式不同,表明CAT1和CAT4 mRNA表达受到发育阶段、品种和肠段的调控。

160 1-day-old parental male Arbor Acre（AA）chicks and 160 1-day-old parental male yellow-feathered chicks were randomly divided into 4 replicates, respectively. Ontogenetic expression of CAT1 and CAT4 mRNA in duodenum,jejunum and ileum of AA chickens and yellow-feathered chickens were determined by relativly quantitative RT- PCR. It was found that：Ontogenetic expression of CAT1 and CAT4 mRNA in duodenum and jejunum was different from ileum. Ontogeny patterns of CAT1 and CAT4 mRNA in duodenum and jejunum were different between AA broiler and yellow-feathered broiler. The abundance of CAT1 mRNA in yellow-feathered broiler decreased from 2 to 58 d and kept the same except decreased on 44 d in AA broiler. The abundance of CAT4 mRNA in yellow-feathered broiler decreased from 2 to 44 d, then increased on 58 d, and kept the same except decreased on 58 d in AA broiler. The abundance of CAT1 mRNA in yellow-feathered broiler ileum decreased from 2 to 44 d, and kept the same except decreased on 44 d in AA broiler. The abundance of CAT4 mRNA in yellow-feathered broiler ileum decreased from 2 to 44 d,then increased on 58 d, and kept the same except decreased on 58 d in AA broiler. These results suggest that：Ontogeny patterns of CAT1 and CAT4 mRNA in duodenum and jejunum was different from in ileum, indicating that the function of amino acid absorption in proximal intestine differed from in distal intestine. Ontogeny of CAT1 and CAT4 mRNA in two strains had the different pattern in duodenum,jejunum, and ileum, and there was difference at the same development stage between AA broiler and yellow-feathered broiler, indicating that CAT1 and CAT4 mRNA expression could be regulated by developmental stage, strain and segment of intestine.