Murakami N, Trenkner E, Elzinga M
Department of Pharmacology, Institute for Basic Research in Developmental Disabilities, Staten Island, New York, New York 10314.
Dev Biol. 1993 May;157(1):19-27. doi: 10.1006/dbio.1993.1108.
Anti-human platelet myosin antibodies and two anti-peptide antibodies, anti-peptide IIA and anti-peptide IIB, which recognize macrophage-type (MIIA) and brain-type (MIIB) isoforms of nonmuscle myosin heavy chain, respectively, were used to study expression of nonmuscle myosin isoforms in various tissues of mice during development. Tissue-specific changes in the relative isoform concentrations were observed by performing immunoblots of crude myosin extracts from nonmuscle and muscle tissues. In fetal and neonatal mouse tissues, the anti-peptide IIB antibodies stained a single band, called MIIB2, while the anti-peptide IIA and anti-platelet myosin antibodies stained a band that migrated faster than MIIB2. In brain, a slower moving band, MIIB1, started to appear at 2 weeks after birth, and in the adult cerebellum it was at least as abundant as MIIB2. In thymus, MIIB2 decreased selectively shortly after birth, while in liver both MIIB2 and MIIA rapidly disappeared, but the isoform(s) detected by anti-platelet myosin antibodies (MIIApla) remained constant. The MIIB2 and MIIA as well as MIIApla found in striated muscles from fetal and neonatal mice decreased to levels that were below the limit of detection by 3 weeks of age. In cryosections of skeletal and cardiac muscles, MIIB2 was localized within the muscle cells, while MIIA and MIIApla were primarily in the blood vessels and capillaries.
抗人血小板肌球蛋白抗体以及两种抗肽抗体，即抗肽IIA和抗肽IIB，分别识别非肌肉肌球蛋白重链的巨噬细胞型（MIIA）和脑型（MIIB）同工型，用于研究发育过程中小鼠各种组织中非肌肉肌球蛋白同工型的表达。通过对来自非肌肉和肌肉组织的粗肌球蛋白提取物进行免疫印迹，观察到相对同工型浓度的组织特异性变化。在胎儿和新生小鼠组织中，抗肽IIB抗体染出一条单一的条带，称为MIIB2，而抗肽IIA和抗血小板肌球蛋白抗体染出一条迁移速度比MIIB2快的条带。在大脑中，一条迁移较慢的条带MIIB1在出生后2周开始出现，在成年小脑中小脑，它至少与MIIB2一样丰富。在胸腺中，MIIB2在出生后不久选择性下降，而在肝脏中，MIIB2和MIIA都迅速消失，但抗血小板肌球蛋白抗体检测到的同工型（MIIApla）保持不变。在胎儿和新生小鼠的横纹肌中发现的MIIB2、MIIA以及MIIApla在3周龄时降至检测限以下。在骨骼肌和心肌的冰冻切片中，MIIB2定位于肌肉细胞内，而MIIA和MIIApla主要位于血管和毛细血管中。
