Isolating And Cloning Of Relevant Genes That Are Differentially Expressed During Chlamydospore Formationg In Trichoderma

Trichoderma is an important group in the biological control of phytopathogenic fungi and is ubiquitous in the environment. They have excellent adaptability and can control the phytopathogene through the diversified mechanisms including competition, mycoparasitism, antibody-secretion and cell lysis. According to statistics, thirty-four percents of the bio-control researches are about Trichoderma. So Trichoderma has unique advantages and study values in the field of bio-control.Now many reports prove that Trichoderma can be used as a method of biological control against plant pathogens. So chlamydospore or conidium of Trichoderma are made to Bio-pesticide and Bio-agent. Conidium has a high productivity but short living period, while chlamydospore has a long living period. Now studying on chlamydospore mostly focus on culture condition of chlamydospore, while little is known about the molecular mechanism of chlamydospore formation. In order to make it clear, we use cDNA-AFLP (cDNA-amplified fragment length polymophism) to analyze the gene differential expression of producing chlamydospore in specific medium.First forty-eight differentiated cDNA fragments were isolated by using ninety-six primer pairs, then through Reverse Northern Blot five positive clones were selected. The results of Northern Blot showed that the five fragments ( Triâ… , Triâ…¡ , Triâ…¢ , Triâ…£, Triâ…¤) were all positive, that indicated the five fragments related to the product of chlamydospore. In order to make clear the structure of the five fragments, we cloned them and analysed their sequence. Then we found clone Triâ…  is similar to Trichoderma hamatum 60S ribosomal protein (P36) gene, clone Tri â…¡ show high homology to gene coding for product with Gibberella zeae PH-1 chromosome 2 hypothetical protein, the predicted product of the clone Triâ…¢ is homologous to the Myc-type basic helix-loop-helix transcription factor Cph2 which regulates hyphal development in Candida albicans .Furthermore , clone Triâ…£ and Triâ…¤ show low homology to previous described gene. They may be the new genes.