驴乳中酪蛋白组成及酪蛋白转录本的差异翻译效率。

Casein composition and differential translational efficiency of casein transcripts in donkey's milk.

机构信息

Department of Agricultural Sciences,University of Naples Federico II,Portici (Naples),Italy.

Department of Veterinary Sciences,University of Pisa,Pisa,Italy.

出版信息

J Dairy Res. 2019 May;86(2):201-207. doi: 10.1017/S0022029919000256. Epub 2019 Apr 30.

DOI:10.1017/S0022029919000256

PMID:31038088

Abstract

The amount of the four caseins (αs1, αs2, β and κ-CN) in donkey milk was evaluated by Urea-PAGE analysis at pH 8.6, followed by immuno-detection with polyclonal antibodies, coupled to densitometric analysis. The results showed the percentage of each casein in decreasing order: β (54.28) > αs1 (35.59) > αs2 (7.19) > κ-CN (2.79). The mRNA quantification of donkey casein transcripts, carried out by RT-qPCR, showed that the average percentage of corresponding gene transcripts (CSN2, CSN1S1, CSN1S2 I and CSN3) was 70.85, 6.28, 14.23 and 8.65, respectively. The observed translation efficiency, assessed as percentage of single milk casein fraction out of single percentage of transcript, was 0.76, 5.66, 0.50 and 0.32, respectively. The analysis of the sequences flanking the start codon, the codon usage frequencies and the coding sequence length might explain, at least in part, the differential transcriptional and translational rate observed among the casein transcripts.

摘要

用 Urea-PAGE 分析 pH8.6 时，驴乳中的四种酪蛋白（αs1、αs2、β 和 κ-CN）的含量，并用与密度分析相结合的多克隆抗体进行免疫检测。结果表明，各酪蛋白的百分率依次降低：β（54.28）>αs1（35.59）>αs2（7.19）>κ-CN（2.79）。通过 RT-qPCR 进行的驴酪蛋白转录本的定量显示，相应基因转录本（CSN2、CSN1S1、CSN1S2 I 和 CSN3）的平均百分率分别为 70.85、6.28、14.23 和 8.65。评估的翻译效率为，单乳酪蛋白分数占单转录本分数的百分比，分别为 0.76、5.66、0.50 和 0.32。启动密码子侧翼序列、密码子使用频率和编码序列长度的分析，至少可以部分解释观察到的酪蛋白转录本之间的差异转录和翻译率。