真菌转基因诱导的内源基因沉默 (PTGS) Isolation of quelling-defective(gde) mutants impaired in posttrans criptional transgene-induced gene silencing in Neurospora crassa, Proc. Natl. Acad. Sci USA 94(1997: These quelling-defective mutants(gde) belonging to three complementation groups have provided insights into the mechanism of posttranscriptional gene silencing in N. crassa. The recessive nature of the gde mutations indicates that the encoded gene products act in trans. we show that when gde genes are mutated in a transgenic-induced silenced strain containing many copies of the transgene the expression of the endogenous gene is maintained despite the presence of transgene sense RNA, the molecule proposed to trigger quelling.真菌转基因诱导的内源基因沉默 (PTGS) Isolation of quelling-defective (qde) mutants impaired in posttrans￾criptional transgene-induced gene silencing in Neurospora crassa, Proc. Natl. Acad. Sci. USA 94 (1997): These quelling-defective mutants (qde) belonging to three complementation groups have provided insights into the mechanism of posttranscriptional gene silencing in N. crassa. The recessive nature of the qde mutations indicates that the encoded gene products act in trans. We show that when qde genes are mutated in a transgenic-induced silenced strain containing many copies of the transgene, the expression of the endogenous gene is maintained despite the presence of transgene sense RNA, the molecule proposed to trigger quelling