Merrifield P A, Sutherland W M, Litvin J, Konigsberg I R
Department of Biology, University of Virginia, Charlottesville.
Dev Genet. 1989;10(5):372-85. doi: 10.1002/dvg.1020100505.
We have raised monoclonal antibodies (Mabs) to myosin heavy chain isoforms (MHCs) that have specific patterns of temporal expression during the development of quail pectoral muscle and that are expressed in very restricted, tissue-specific patterns in adult birds. We find that an early embryonic, a perinatal, and an adult-specific, fast myosin heavy chain are co-expressed at different levels in the pectoral muscle of 8-12 day quail embryos. The early embryonic MHC disappears from the pectoral muscle at approximately 14 days in ovo, whereas the perinatal MHC persists until 26 days post-hatching. The adult-specific MHC accumulates preferentially and eventually completely replaces the other isoforms. These Mabs cross-react with the homologous isoforms of the chick and detect a similar pattern of MHC expression in the pectoral muscle of developing chicks. Although the early embryonic and perinatal MHC isoforms recognized by our Mabs are expressed in the pectoral muscle only during distinct developmental stages, our Mabs also recognize MHC isoforms present in the heart and extraocular muscle of adult quail. Immunofingerprinting using Staphylococcus aureus protease V8 suggests that the early embryonic and perinatal MHC isoforms that we see are strongly homologous with the adult ventricular and extraocular muscle isoforms, respectively. These observations suggest that at least three distinct MHC isoforms, which are normally expressed in adult muscles, are co-expressed during the early development of the pectoral muscle in birds. In this respect, the pattern of expression of the MHCs recognized by our Mabs in developing, fast muscle is very similar to the patterns described for other muscle contractile proteins.
我们已经制备了针对肌球蛋白重链同工型（MHCs）的单克隆抗体（Mabs），这些同工型在鹌鹑胸肌发育过程中具有特定的时间表达模式，并且在成年鸟类中以非常有限的、组织特异性模式表达。我们发现，一种早期胚胎型、一种围产期型和一种成年特异性的快速肌球蛋白重链在8至12日龄鹌鹑胚胎的胸肌中以不同水平共表达。早期胚胎型MHC在卵内约14天时从胸肌中消失，而围产期MHC持续存在至孵化后26天。成年特异性MHC优先积累并最终完全取代其他同工型。这些单克隆抗体与鸡的同源同工型发生交叉反应，并在发育中的小鸡胸肌中检测到类似的MHC表达模式。尽管我们的单克隆抗体识别的早期胚胎型和围产期MHC同工型仅在不同的发育阶段在胸肌中表达，但我们的单克隆抗体也识别成年鹌鹑心脏和眼外肌中存在的MHC同工型。使用金黄色葡萄球菌蛋白酶V8进行免疫指纹分析表明，我们所观察到的早期胚胎型和围产期MHC同工型分别与成年心室和眼外肌同工型高度同源。这些观察结果表明，至少三种通常在成年肌肉中表达的不同MHC同工型在鸟类胸肌的早期发育过程中共表达。在这方面，我们的单克隆抗体识别的MHCs在发育中的快速肌肉中的表达模式与其他肌肉收缩蛋白所描述的模式非常相似。
