Studies on the origin of body plan of multicellular animals

本研究旨在利用胶原蛋白及其基因作为探针，积累多细胞动物起源的知识。人们普遍认为，从最原始的海绵到最进化的人类，所有的多细胞动物都含有胶原蛋白作为主要蛋白质之一，但植物和单细胞生物都不含胶原蛋白，这表明胶原蛋白及其基因在多细胞生物向多细胞动物的进化过程中发挥了重要作用。作者从比较的角度对胶原蛋白及其基因进行了2年的研究，以期在理解动物进化过程中多细胞的形成过程方面取得新的进展。主要结果如下：1。海胆胶原蛋白及其基因的研究。从两种海胆（hemicentrrotus pml）的实验中纯化胶原蛋白。樱桃和StrpLn loqentrotus紫癜…鉴定出三个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 Hpcol1。测定了Hpcol1的全长序列。中生动物胶原蛋白基因的研究。对身体结构被认为是动物中最简单的中zozoati Dicyema misakiense的基因组DNA进行了Southern blotting分析，发现其存在与lipcoll同源的碱基序列。人们发现这种动物不含这种基因序列。海绵胶原蛋白的研究发现，在游离的海绵细胞重新聚集的过程中，可以合成分子量为581的胶原蛋白肽。这种肽似乎在海绵细胞的组织过程中起着关键作用。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，从三个不同的器官中获得；皮肤，肺和心脏的体外培养。发现成纤维细胞在增殖速率、胶原凝胶收缩能力和蛋白质合成模式等方面表现出器官依赖性。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