鄱阳湖日本沼虾幼体发育及其同工酶研究

<title>Larval development and isozymes analysis inshrimp Macrobrachium nipponensis in Poyang Lake

对鄱阳湖日本沼虾(Macrobrachiumnipponensis)幼体发育的5个阶段即Z0、Z1、Z3、Z5～Z6及Z9～Z11期进行观察,分析乳酸脱氢酶(LDH)、酯酶(EST)、苹果酸脱氢酶(MDH)同工酶谱带变化。结果表明,各期间幼体形态均有明显变化,幼体蜕皮次数随发育快慢不同,发育快的需9次蜕皮完成变态发育过程,慢的则需14次;LDH酶谱在5个发育阶段各有5条带,仅酶活性有强弱变化;EST酶谱不仅条带数从2条增加到9条,酶活性也有明显变化,EST1和EST3在5个阶段都出现,且酶活性逐渐升高;MDH酶谱共出现6条带,MDH1和MDH4分布延伸时间跨度大,酶活性高,可看作主带。因此日本沼虾变态发育过程中同工酶谱带随变态发育而变化,反映了不同组织器官细胞组成和不同组织中不同同工酶的活性和出现顺序,可作为鉴别种属特异性和发育阶段特异性的一项生化指标。

<Abstrcat> The female parent Marobrachium nipponensis were collected from Poyang Lake, body length 4-6 cm. The hatched larvae from the parents were observed at 5 different developing stages, which were Z0, Z1, Z3, Z5-Z6 and larval stage. For the developingfast larvae, 9 times of molt are needed to complete the metamorphic process, but for the slow, 14 times are needed. For the larvae at the 5 stages, each has 5 bands on LDH electropherograms with identical rate of mobility, but the activities fluctuate among them. At stage 1,two EST electropherogram bands present, and at stages 2, 3 and 4, three bands present; at stage 5, nine bands present, all accompanied with obvious changes of enzyme activities. The MDH electropherograms have 6 bands, among which MDH1 and MDH2 are the main bands for their high enzyme activities and wide prolonged time distribution. The complex changes of isozyme electropherograms in M. nipponensis at different developing stages reveal the different isozyme activities and presenting sequence in different organ cells and these changes can be used as the biochemical indexes to identify the specificity of certain species and certain development stage.