Studies on the origin of body plan of multicellular animals

本研究利用胶原蛋白及其基因作为探针，对多细胞动物的起源进行了研究。从最原始的物种海绵到最进化的物种人类，都含有胶原蛋白，这是一种主要的蛋白质，但植物和单细胞生物都不含有，这表明胶原蛋白及其基因在多细胞生物向多细胞动物进化的过程中起着重要作用。作者从比较的角度对胶原蛋白及其基因进行了两年的研究，以期对动物进化过程中多细胞生物的建立过程有一个新的认识。主要结果如下所述。海胆胶原蛋白及其基因的研究：从两种海胆（Hemicentrotus pml）中分离纯化胶原蛋白。黑色素性紫癜 ...更多信息 tus鉴定了三条α链，分别命名为α 120、α 90和α 140。克隆了编码α 120和α 140的cDNA Hpcol 1。测定了Hpcol 1的全长序列.中生动物胶原基因的研究用Southern印迹法分析了中生动物中身体结构最简单的米崎双囊线虫（Dicyema misakiense）的基因组DNA中是否存在与Lipcoll同源的碱基序列。结果发现，该动物不含这样的序列。3.海绵胶原蛋白的研究发现，在分离的海绵细胞的再聚集过程中合成了分子量为581的胶原肽。该肽似乎在海绵细胞的组织过程中发挥了一些关键作用。不同器官成纤维细胞的比较研究成纤维细胞是合成胶原蛋白的主要细胞种类之一，从三种不同的器官：皮肤、肺和心脏获得并体外培养。结果发现，成纤维细胞的增殖速度，胶原凝胶收缩能力和蛋白质合成模式的器官依赖性的字符。少

The present study lias beeti uridertaleii as orie of the efforts to accumulate knowledge ori the origin of multicellular animals utilizing collagen and its genes as probes. It has beeti generally l (now that all title multicellular animals from the most primitive species, sponges, to tie most evolved one, human, contain collagen-as one of the major proteins, but neither plants nor unicellular organisms do not, suggesting that collagen and its genes play some important role-, s during evolutiotin from multi-icellular organisms to multicellular animals. The present author has developed for 2 years studies on collagen and its genes from the comparative point of view to malke a progress in understanding the process of establishment of multicellularity during animal evolution. The major results are described below.1. Studying on collagen and its genes of sea urchins.Collagen was purified from the tests of two species of sea urchin, Hemicentrotus pml. cherrimus and StrpLn loqentrodus purpura … More tus. Three alpha chains were identified and named alpha 120, alpha 90 and alpha 140, respectively. cDNA, Hpcol1, was cloned, which codes alpha 120 and alpha 140. Sequences of Hpcol1 were determined in its full length.2. Studies on collagen genes of Mesozoans.Genome DNA of Dicyema misakiense, a Mesozoati, whose body structure is believed to be simplest among animals, was analyzed for ttie presence of base sequences homologous to those of lipcoll with the Southern blotting. It was found that the animal does not contain such sequences.3. Studies on sponge collagenCollagen peptides with a molecular weight or 581 (were found to be synthesized during reaggregation of dissociated sponge cells. This peptide seems to play some critical roles during organization of sponge cells.4. Comparative studies of fibroblasts from different organs.Fibroblasts, one of tile major cell species that synthesize collagen, were obtained from three different organs ; skin, lung and heart and cultured in vito. It was found that fibroblasts show organ-dependent characters as to rate of proliferation, collagen gel contracting ability and protein synthesis patterns. Less