Abstract: Themolecular phylogeny of four strains ofDaphniopsistibetanaSars(NMKC,SLC,BG and SLM)were studied based onmitochondrial12S rRNA gene sequences.Themolecular evolution ofD.tibetanawere dicussed by means of 12S rRNA gene sequence of the corresponding sequences of 7 other species ofDaphniaCladocera from GenBank.The results showed that the mean concentration of A,T,G,C for 4 strainsD.tibetanaof 12 SrRNA gene sequenceswere 31.9%,32.45%,17.33%and 17.95%,respectively.The base pair concentrations were 64.35%in A+T and 35.28%in G+C.These were accordance with feature of higher A,T concentration in Arthropoda animals.There were significant differences betweenD.tibetanaand other species of cladocera,according to the results of genetic distance and using UPGMA cluster analysis in the Mega 4 software package procedures,indicating thatD.tibetanahas an unique position in the research of biology of Cladocera.The highestgenetic similarity were between NMKC strain and SLC strain aswell as between NMKC strain and BG strain,the genetic distance between NMKC strain and BG strain was the lowest in 0.0126,and highestwas between SLM strain and BG strain in 0.0199.Itwas indicated that the interspecific difference was very significant,and the intraspecific difference is unconspicuous compared with other species ofDaphniasuchas.All above shows thatD.tibetanaSars has high levels of genetic diversity,and mitochondrial 12S rRNA can provide the reliable evolutionary information,and it can be used asmolecularmarkers for phylogeny events.In addition,DaphniopsistibetanaSars andDaphniatibetanawere proved to be different species in molecular aspects by thismethod.
赵文, 李睿. 4个品系西藏拟溞12S rRNA基因序列及其分子进化研究[J]. 大连海洋大学学报, 2012, 27(4): 300-305.
ZHAOWen, LIRui. M olecular phylogeny of four strains of Daphniopsis tibetana Sars based on m itochondrial 12S rRNA gene sequences. Journal of Dalian Ocean University, 2012, 27(4): 300-305.
2012, Vol. 27 
