Molecular Characterization of Transgenic Soybean Overexpressing the GM-RLK3

Soybean (Glycine max L.) GM-RLK3 is a receptor-like kinase gene, which shares similarity with Arabidopsis thaliana BAM1, a CLAVATA family gene. BAM1, BAM2, and members of the CLAVATA family are involved in meristem fate and control of cellular differentiation. Stable transgenic plants for overexpression of GM-RLK3 were developed using immature cotyledon explants from soybean cultivar Jack and the binary vector pH2GW7 containing GM-RLK3 gene mobilized into Agrobacterium tumefaciens strain KYRT1 by electroporation. Southern blot hybridization confirmed that homozygous transgenic plants of the T3 generation carried a stable integrated transgene (GM-RLK3). The overexpression level of GM-RLK3 was examined by qRT-PCR in different plant tissues including roots, cotyledons, unifoliolates, trifoliolates, stems, flowers and pods from both transgenic and the wild type. QRT-PCR demonstrated the overexpression of this transgene in different tissues, and showed that GM-RLK3 was overexpressed in unifoliolate tissues (52 fold increase) with lower expression in pod tissues (7.7 fold increase). To examine the possible role(s) of this gene in soybean defense to biotic and abiotic stress, progress is being made to challenge transgenic plants by both stresses. Additionally, RNA-seq profiled the transcriptome of both transgenic and wild type to decipher signaling pathways during overexpression of Gm-RLK3 in soybean.