EXPRESSION OF ALPHA-SM ACTIN IN TERRESTRIAL ECTOTHERMIC VERTEBRATES
EXPRESSION OF ALPHA-SM ACTIN IN TERRESTRIAL ECTOTHERMIC VERTEBRATES
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DOI：
10.1007/bf00417867
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发表时间：
1995-09-01
影响因子：
3.6
通讯作者：
PASCOLINI, R
中科院分区：
文献类型：
--
作者：
DIROSA, I;PANARA, F;PASCOLINI, R
吸热型脊椎动物的α-平滑肌肌动蛋白可被抗α-SM-1的单抗选择性识别。对该抗体的免疫反应性已被证明定位于NH2末端序列Ac-EEED(Chaponnier等人。(1994年)。在陆生外温脊椎动物中，对两栖动物(Triturus ual garis、Rana esculenta)和三种爬行动物(Pseudemys Scripta elegans、Natrix Natrix、Podarcis syla)进行了筛选，以观察它们的血管和内脏平滑肌是否被抗αSM-1染色。在所有被测试的样本中，用抗αSM-1免疫修饰的组织提取物的Western-Blot分析显示，单一的多肽链与牛αSM肌动蛋白具有相同的凝胶迁移率。与两栖和爬行动物组织提取物的结合可被合成肽ACEED抑制，但不能像哺乳动物那样被抑制。αSM肌动蛋白在受试物种的血管和内脏平滑肌细胞中均有表达。大、小血管中膜用抗αSM-1标记。在茎、ACh和肠中，肌层和粘膜的外纵层和内环层被染色。此外，对上皮下层的肌成纤维细胞进行了标记。在甲鱼(P.cripta elegans)内脏平滑肌细胞中检测到该等肌动蛋白的表达更为有限，这可能与消化系统参与呼吸活动有关。这些数据表明，在脊椎动物的进化中，αSM肌动蛋白的出现时间比之前提出的要早。
alpha-Smooth muscle (alpha SM) actin of endothermic vertebrates is selectively recognized by the monoclonal antibody anti-alpha SM-1. Immunoreactivity to this antibody has been shown to be localized in the NH2-terminal sequence Ac-EEED (Chaponnier et al. 1994). Among terrestrial ectothermic vertebrates, two amphibian (Triturus vulgaris, Rana esculenta) and three reptilian species (Pseudemys scripta elegans, Natrix natrix, Podarcis sicula) were screened to investigate if their vascular and visceral smooth muscles were stained by anti-alpha SM-1. In all the specimens tested, Western-blot analysis of tissue extracts immunodecorated with anti-alpha SM-1 revealed a single polypeptide chain having the same electrophoretic mobility as bovine alpha SM actin. The binding to amphibian and reptilian tissue extracts was inhibited by the synthetic peptide Ac-EEED, but not Ac-DEED, as occurs in mammals. alpha SM actin expres sion was found in vascular and visceral smooth muscle cells of the species tested. The media of small and large blood vessels was labelled by anti-alpha SM-1. In the stem ach and intestine the outer longitudinal and inner circular layers of the muscularis and of the muscularis mucosae were stained. In addition, myofibroblasts of the subepithelial layer were labelled. A more restricted expression of this isoactin was detected in turtle (P. scripta elegans) visceral smooth muscle cells, which may be related to the involvement of the digestive system in respiratory activity. These data suggest that in vertebrate evolution alpha SM actin arose earlier than previously proposed.