Mammary transcriptome analysis of lactating dairy cows following administration of bovine growth hormone.
Mammary transcriptome analysis of lactating dairy cows following administration of bovine growth hormone.
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DOI：
10.1017/s1751731116000987
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发表时间：
2016-05
期刊：
影响因子：
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通讯作者：
S. McCoard;A. Hayashi;Q. Sciascia;J. Rounce;B. Sinclair;W. McNabb;N. Roy
中科院分区：
文献类型：
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作者：
S. McCoard;A. Hayashi;Q. Sciascia;J. Rounce;B. Sinclair;W. McNabb;N. Roy
生长激素(GH)在哺乳期反刍动物中的生乳作用已得到很好的证实；然而，调节这些作用的机制还不是很清楚。这项研究的第一个目标是确定生长激素对主要酪蛋白和乳清蛋白合成的影响。第二个目标是确定可能参与调节生长激素对乳汁合成影响的基因和途径。非妊娠奶牛(n=4头/组)在哺乳期中后期皮下一次性注射市售生长激素缓释剂(乳酸三丁酯®)或生理盐水溶液(对照组)。在注射后第6天采集乳样进行成分分析，并采集乳小叶-肺泡组织。用22000个牛互补DNA微阵列或定量聚合酶链式反应(QPCR)评估基因表达谱，并用qPCR验证微阵列。除α-乳清蛋白产量比对照组提高70%外，GH组奶牛的主要酪蛋白和乳清蛋白产量均提高了32%~41%。GH处理有增加α-乳清蛋白浓度的趋势，但对任何主要乳蛋白的浓度没有影响。与对照相比，除α-S2-酪蛋白外，其他主要乳清和酪蛋白基因的信使核糖核酸丰度增加，这与生长激素对产奶量的积极作用是一致的。生长激素处理影响与细胞生长和增殖、转录和翻译调节、肌动蛋白细胞骨架信号、脂质代谢和细胞死亡有关的基因的mRNA丰度。这项研究为细胞信号提供了新的见解，该信号可能参与了生长激素对奶牛乳腺产奶量的影响。
The galactopoietic effect of growth hormone (GH) in lactating ruminants is well established; however the mechanisms that mediate these effects are not well understood. The first objective of this study was to determine the effect of GH on the synthesis of the major casein and whey proteins. The second objective was to identify the genes and pathways that may be involved in mediating the effect of GH on milk synthesis. A single subcutaneous injection of a commercially available slow release formulation of GH (Lactatropin®), or physiological saline solution (control) was administered to non-pregnant dairy cows (n=4/group) in mid-late lactation. Milk samples were collected for composition analysis and mammary lobulo-alveolar tissue was collected postmortem 6 days post injection. Gene expression profiles were evaluated using either a 22 000 bovine complementary DNA microarray or quantitative PCR (qPCR), and microarrays were validated by qPCR. The yield of all the major casein and whey proteins was increased 32% to 41% in GH-treated cows, with the exception of α-lactalbumin yield which was elevated by 70% relative to controls. Treatment with GH treatment tended to increase the concentration of α-lactalbumin but had no effect on the concentration of any of the major milk proteins. Messenger RNA (mRNA) abundance of the major whey and casein genes, with the exception of α-s2-casein, was increased in response to GH compared with controls, which is consistent with the positive effect of GH on milk production. Treatment with GH treatment influenced the mRNA abundance of genes involved in cell growth and proliferation, transcriptional and translational regulation, actin cytoskeleton signalling, lipid metabolism and cell death. This study has provided new insights into the cell signalling that may be involved in mediating the effect of GH on milk production in the mammary gland of lactating dairy cows.