Isolation of development-related genes in somatic embryo radicle of carrot (Daucus carota L.) using modified cDNA RDA

【摘要】 <正> Using modified cDNA RDA capitalizing on the high affinity of streptavidin for biotin and magnetic-absorption-based separation, we have obtained four bands of specifically expressed cDNA in the carrot somatic embryo deregulated for 12 h, which were designated as NR-1, NR-2, NR-3 and NR-4, respectively. As revealed by homology analysis of their DNA sequences after cloning them into pBS, remarkable homology was demonstrated in NR-2, NR-3 and NR-4 with the genes coding for LEA (late embryogenesis abundant protein), Dna J and xyloglucan endo-trans-glycosylase in plants. On the other hand, NR-1 showing no homology with any known sequence may have come from unknown genes. Using 32P-labeled NR-1 as probe, hybridization with cDNA fragment population has shown that we have actually cloned a new gene fragment related to radicle development. As shown by further Southern hybridization, these genes may be present in carrot genome in the form of single or low copies.更多还原

【Abstract】 Using modified cDNA RDA capitalizing on the high affinity of streptavidin for biotin and magnetic-absorption-based separation, we have obtained four bands of specifically expressed cDNA in the carrot somatic embryo deregulated for 12 h, which were designated as NR-1, NR-2, NR-3 and NR-4, respectively. As revealed by homology analysis of their DNA sequences after cloning them into pBS, remarkable homology was demonstrated in NR-2, NR-3 and NR-4 with the genes coding for LEA (late embryogenesis abundant protein), Dna J and xyloglucan endo-trans-glycosylase in plants. On the other hand, NR-1 showing no homology with any known sequence may have come from unknown genes. Using 32P-labeled NR-1 as probe, hybridization with cDNA fragment population has shown that we have actually cloned a new gene fragment related to radicle development. As shown by further Southern hybridization, these genes may be present in carrot genome in the form of single or low copies.更多还原