The Impact Of Environmental Stress On The Expression Of Genetic Differences Of The Different Categories Of Single-nest Class Rotifers

In order to study the molecular mechanism of sexual reproduction of the Monogononta in gene expression , We obtained amictic female, mictic female and male by temperature stimulating, and then studied their differences in gene expression by Fluorescent Differential Display-PCR. The following results were obtained:(1) The percentage of mictic female in the offspring is the highest in culture that underwent sudden cold shock (SS) treatment for 4h.(2) We extracted the RNA from amictic female, mictic female and male of Brachionus calyciflorus with Trizol kit. In addition, we found that at least 300 females were needed in the RNA extraction.(3) Thirty-four differentially expressed cDNA fragments were obtained from twenty DD-PCR reactions. Eighteen differentially expressed cDNA fragments were amplified in reamplification reactions. About 1/2 of the thirty-four differentially expressed cDNA fragments could not be reamplified, which might be false positive. The results showed that there were remarkable differences in gene expression among amictic female, mictic female and male.(4) We cloned and sequenced the sixteen differentially expressed DNA fragments. These sequences were H7-1, H7-2, F7-1, F7-2 , F7-3 , F7-4, F7-6 , H8-1, H8-4, H8-6,X9-1, X9-2 , H10-1, H10-3, X11-1 and F13-1. The alignment of these sequences through NCBI BLAST database revealed that H7-1 had high homology with Brachionus calyciflorus internal transcribed spacer 1, internal transcribed spacer 2, 5.8S ribosomal RNA gene and 18S rRNA gene. But the others did not match any reported genes and may be some unknown genes.