Gene expression identifies metabolic and functional differences between intramuscular and subcutaneous adipocytes in cattle
Gene expression identifies metabolic and functional differences between intramuscular and subcutaneous adipocytes in cattle
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DOI：
10.1186/s12864-020-6505-4
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发表时间：
2020-01-28
期刊：
影响因子：
4.4
通讯作者：
Greenwood, Paul L.
中科院分区：
文献类型：
--
作者：
Hudson, Nicholas J.;Reverter, Antonio;Greenwood, Paul L.
背景资料：本研究采用全基因组筛选基因表达，以更好地了解有商业价值的肌内脂肪（IMF）和商业浪费的皮下（SC）脂肪库之间的代谢和功能的差异，在Bos taurus beauty.Results：我们证实了许多研究结果以前在生化水平，并取得了新的发现。基本的脂肪生成机制，如编码限速乙酰辅酶A羧化酶和脂肪酸合成酶的ACACA和FcB，在IMF中以低1.6-1.8倍的水平表达，与先前的发现一致。与SC相比，如预期的，包括限速酶VL 6的FA延伸途径在IMF中也协同下调。编码乙酰辅酶A合成酶的ACSS 2在IMF中的表达降低2倍，这与先前使用放射性同位素掺入测定的IMF中脂肪生成使用的乙酸盐比SC少一致。SC贮库中脂肪饱和度的降低反映为编码Delta 9去饱和酶的SCD基因的表达增加2.4倍。令人惊讶的是，CH 25 H编码的胆固醇25羟化酶是类似的36倍上调IMF相比，SC。此外，其在整个肌肉组织中的表达出现代表的比例代表牛大理石花纹脂肪细胞。这组观察结果促使对表现出不同IMF的8头牛的血浆中的一组氧固醇（胆固醇的氧化形式）进行定量。使用液相色谱-质谱法（LC-MS），我们发现几个氧化甾醇的水平显着相关的多大理石花纹测量整个肌肉组织，但（只有一个例外）没有其他尸体phenotypes.Conclusions：这些数据建立在我们的反刍动物脂肪库生物学的分子理解，并建议氧化甾醇代表一个有前途的循环生物标志物牛大理石花纹。
Background: This study used a genome-wide screen of gene expression to better understand the metabolic and functional differences between commercially valuable intramuscular fat (IMF) and commercially wasteful subcutaneous (SC) fat depots in Bos taurus beef cattle.Results: We confirmed many findings previously made at the biochemical level and made new discoveries. The fundamental lipogenic machinery, such as ACACA and FASN encoding the rate limiting Acetyl CoA carboxylase and Fatty Acid synthase were expressed at 1.6-1.8 fold lower levels in IMF, consistent with previous findings. The FA elongation pathway including the rate limiting ELOVL6 was also coordinately downregulated in IMF compared to SC as expected. A 2-fold lower expression in IMF of ACSS2 encoding Acetyl Coenzyme A synthetase is consistent with utilisation of less acetate for lipogenesis in IMF compared to SC as previously determined using radioisotope incorporation. Reduced saturation of fat in the SC depot is reflected by 2.4 fold higher expression of the SCD gene encoding the Delta 9 desaturase enzyme. Surprisingly, CH25H encoding the cholesterol 25 hydroxylase enzyme was similar to 36 fold upregulated in IMF compared to SC. Moreover, its expression in whole muscle tissue appears representative of the proportional representation of bovine marbling adipocytes. This suite of observations prompted quantification of a set of oxysterols (oxidised forms of cholesterol) in the plasma of 8 cattle exhibiting varying IMF. Using Liquid Chromatography-Mass Spectrometry (LC-MS) we found the levels of several oxysterols were significantly associated with multiple marbling measurements across the musculature, but (with just one exception) no other carcass phenotypes.Conclusions: These data build on our molecular understanding of ruminant fat depot biology and suggest oxysterols represent a promising circulating biomarker for cattle marbling.