Abstract :
Genetic recombination is a fundamental process in living cells. Studies on homologous recombination have potential implementation in gene targeting and the development of apomictic varieties in plants with the avoidance of meiotic reduction during embryo sac formation. Recombination is clearly not a meiosis-specific process in any organism. In all explored tissues, recombinant genes that were not meiosis-specific, or may function in both meiosis and mitosis. The DMC1 recombinase gene sequences have been reported only in a few plant species. After assigning the recombinational properties on Zea mayse DMC1for the first time by in silico analysis, the PCR product containing the 400 bps from 3ʹ-end (exon No.15) of dmc1 was cloned into pHANNIBAL then pART27 plasmids in sense, antisense and the both orientation as RNAi cassettes with a pyruvate dehydrogenase kinase (pdk) intron as spacer, the CaMV35S promoter and the OCS terminator in sense for the immature embryo of maize callus transformation. Total RNAs were extracted from bombarded calli 3 and 7 days after shooting along with some specific tissues of maize as control. RT-PCR amplification was performed on first cDNA strands using gene specific primer sets of dmc1 gene and actin as an internal control to normalize the results. Semi-quantitative RT-PCR and Real Time RT-PCR analyses showed significant differences on dmc1 expressions between transformed and control calli resulting that the RNAi construct has been succeeded on dmc1 gene silencing in calli of maize. The maize meiotic gene, dmc1 expression was detected in both reproductive and vegetative tissues.
