Mechanisms of regeneration of insect imaginal discs.

1. 石棺影像椎间盘离体再生定位价值的恢复。将表达wingles （wg）基因的Sarcophaga象盘的1/4扇区去除，其余部分在2.5 × 10^<-8>M 20-羟基蜕皮素存在下培养，其形态得以恢复。在这里，我们分离了Sarcophaga wg基因的cDNA，并分析了在20-羟基蜕皮的情况下，当图像椎间盘的剩余部分培养时，wg表达所显示的丢失的位置值是否恢复。结果，在再生区域检测到wg基因的表达，表明图像椎间盘的体外再生与体内再生相似，涉及位置值的恢复。美洲蟑螂再生腿凝集素基因cDNA克隆及表达分析。两种体液凝集素，称为26kda凝集素和再生素，在美洲蟑螂再生的腿上短暂出现。其中，26-kDa凝集素在再生素中期定位于再生腿表皮周围，而再生素在再生肌肉细胞晚期定位于再生肌肉细胞周围。在这项研究中，我们分离了这些凝集素的cdna并确定了它们的初级结构。结果发现，这些凝集素是c型（Ca^<2+>-依赖）凝集素，并与彼此具有约50%的序列一致性。这些结果表明，这些凝集素属于同一蛋白家族，在腿部再生中发挥不同的作用。再生素基因在再生表皮中有短暂表达，提示其通过表皮合成和分泌，以旁分泌方式形成肌肉细胞。这是首次鉴定出参与昆虫器官再生的分子（20-羟基蜕皮素和体液凝集素），将为更好地理解器官再生的分子机制提供重要线索。少

1. Restoration of positional values of Sarcophaga imaginal discs on regeneration in vitro.When the 1/4 sectors of imaginal discs of Sarcophaga expressing wingles (wg) gene are removed and the remeining parts are cultured in the presence of 2.5 x 10^<-8>M 20-hydroxyecdyson, restoration of their morphology occurrs. Here, we isolated a cDNA for the Sarcophaga wg gene, and analyzed whether the lost positional values revealed by wg expression were restored when the remaining parts of imaginal discs were cultured in the presence of 20-hydroxyecdyson. As results, expression of the wg gene was detected in the regenrated areas, indicating that regeneration of imaginal discs in vitro minics in vivo regeneration in that it involves restoration of positional values.2.cDNA cloning and analysis of expression of the gene for lectins that localize in the regenerating legs of American cockroach.Two humoral lectins, termed 26-kDa lectin and regenectin, appear transiently in the regenerating legs of Amer … More ican cockroach. Among them, 26-kDa lectin localizes around epidermis of the regenerating legs in the middle stage of regeneratin, whereas regenectin localizes around regenetating muscle cells in the late stage. In this study, we isoalted cDNAs for these lectins and determined their primary structures. As results, these lectins were found to be C-type (Ca^<2+>-dependent) lectins and shares about 50% sequence identities with eact other. these results suggest that these lectins belong to the same protein family and play different roles in leg regeneration. The gene for regenectin was found to express transiently in the regenerating epidermis, suggesting that it functions in the formation of muscle cells in a paracrine manner by synthesized and secreted by the epidermis.This is the first instance that identified molecules (20-hydroxyecdyson and humoral lectins) that is involved in the regeneration in insects and woud be an important clue to better undrstand the molecular mechanisms of organ regeneration. Less