Expressed sequence tags (ESTs) represent the transcribed fraction of complementary DNA from organism's cDNA library. Randomly selected 910 clones were sequenced from mud loach, Misgurnus mizolepis G㉨nther, 1888 cDNA library constructed using mRNA extracted from liver. Of 910 mud loach liver cDNA clones analyzed into similarity that 94.9% clones significant similarity with sequeces from GenBank (e-value<10-3) and 6.2% showed poor similarity (e-value◎10-3) or no matched any sequence in GenBank. The percentage of singleton (unique sequence) represented 38.6% in this ESTs database. Analysis of organisms were stand for the best hit in this ESTs showed that 82.6% matched with fish entries. Functional clustering of this ESTs based on gene expression. Functional groups consisted of 10 classes. In this libraries, the class ？？ (immune function, chaperones and defense mechanism) and class ？？ (general metabolism) was the largest groups with an average of 18.5% and 18.9%, respectively. We selected 467 unigene clones from mud loach ESTs which was fundamental basis of this database.
Mud loach male were sex reversed using estradiol-17┑(E2). The survival of fish during treatment was dose and duration independent. But, growth performance were unaffected dose and duration. Acute symptoms showed that exposure to E2 for short times and affected death. On the other hand, chronical symptoms revealed gall-bladder different in treatment groups that exposure to E2 for long times. Morphologically, however, they were not changed liver and gonad.
cDNA microarray signal revealed relation to stress and physiological unbalance genes that highly increase expression than other genes. Conversely, relation to general metabolism genes were highly decrease expression than other genes.
Consequently, the objective of this study was to analysis of gene expression in mud loach liver, cDNA microarray using this EST database approach to survey of the effects of pollutant E2 on an evrionmentally relevant, male mud loach observation of changed histology and morphology.