Dube Dipak K, Dube Syamalima, Abbott Lynn, Elsekaily Omar, Randhawa Samender S, Sanger Jean M, Sanger Joseph W, Poiesz Bernard J
Department of Medicine, SUNY Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA.
Department of Cell and Developmental Biology, SUNY Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA.
Biochem Res Int. 2023 Jan 24;2023:1303500. doi: 10.1155/2023/1303500. eCollection 2023.
Old world monkeys separated from the great apes, including the ancestor of humans, about 25 million years ago, but most of the genes in humans and various nonhuman primates are quite similar even though their anatomical appearances are quite different. Like other mammals, primates have four tropomyosin genes (TPM1, TPM2, TPM3, and TPM4) each of which generates a multitude of TPM isoforms via alternative splicing. Only TPM1 produces two sarcomeric isoforms (TPM1 and TPM1), and TPM2, TPM3, and TPM4 each generate one sarcomeric isoform. We have cloned and sequenced TPM1, TPM1, TPM2, TPM3, and TPM4 with RNA from cynomolgus (Cyn) monkey hearts and skeletal muscle. We believe this is the first report of directly cloning and sequencing of these monkey transcripts. In the Cyn monkey heart, the rank order of TPM isoform expression is TPM1 > TPM2 > TPM1 > TPM3 > TPM4. In the Cyn monkey skeletal muscle, the rank order of expression is TPM1 > TPM2 > TPM3 > TPM1 > TPM4. The major differences in the human heart are the increased expression of TPM1, although TPM1 is still the dominant transcript. In the Cyn monkey heart, the only sarcomeric TPM isoform at the protein level is TPM1. This is in contrast to human hearts where TPM1 is the major sarcomeric isoform but a lower quantity of TPM1, TPM2, and TPM3 is also detected at the protein level. These differences of tropomyosin and/or other cardiac protein expression in human and Cyn monkey hearts may reflect the differences in physiological activities in daily life.
旧世界猴大约在2500万年前与包括人类祖先在内的类人猿分道扬镳，尽管人类和各种非人类灵长类动物的解剖外观有很大差异，但它们的大多数基因却非常相似。与其他哺乳动物一样，灵长类动物有四个原肌球蛋白基因（TPM1、TPM2、TPM3和TPM4），每个基因通过可变剪接产生多种TPM异构体。只有TPM1产生两种肌节异构体（TPM1和TPM1），而TPM2、TPM3和TPM4各自产生一种肌节异构体。我们已从食蟹猴的心脏和骨骼肌中提取RNA，对TPM1、TPM1、TPM2、TPM3和TPM4进行了克隆和测序。我们相信这是首次直接克隆和测序这些猴转录本的报告。在食蟹猴心脏中，TPM异构体表达的顺序为TPM1＞TPM2＞TPM1＞TPM3＞TPM4。在食蟹猴骨骼肌中，表达顺序为TPM1＞TPM2＞TPM3＞TPM1＞TPM4。人类心脏的主要差异在于TPM1表达增加，尽管TPM1仍是主要转录本。在食蟹猴心脏中，蛋白质水平上唯一的肌节TPM异构体是TPM1。这与人类心脏不同，在人类心脏中TPM1是主要的肌节异构体，但在蛋白质水平上也检测到少量的TPM1、TPM2和TPM3。人类和食蟹猴心脏中原肌球蛋白和/或其他心脏蛋白表达的这些差异可能反映了日常生活中生理活动的差异。
