title: Differentially expressed genes related to symbiotic association in a supernodulating soybean mutant and its wild-type.
abstract: SUMMARY To understand the molecular basis of symbiotic association, a cDNA-AFLP technique was used to identify differentially expressed transcripts between a supernodulating soybean mutant, SS2-2, and its wild-type, Sinpaldalkong 2. As sources of cDNA-AFLP templates, trifoliates of 2-week-old plants were collected 1 week after Bradyrhizobium japonicum inoculation. A total of 147 bands out of 4000 amplicons were recognized as differentially expressed fragments, with 40 transcript-derived fragments (TDFs) in SS2-2 and 65 TDFs in Sinpaldalkong 2. Qualitative and quantitative real-time RT-PCR assays suggested that the expression patterns of genes in both genotypes were clearly differentiated. TDFs homologous to nodulin (65S2) and a putative senescence-associated protein (9S1) were up-regulated in SS2-2, whereas Sinpaldalkong 2 showed up-regulation of a receptor-like kinase (48sin1) and a kinase-like protein (17sin1). This indicates that different genes may be involved in regulation of the symbiotic programme that distinguishes SS2-2 from its wild-type. A TDF showing a change in a single base from A (Sinpaldalkong 2) to T (SS2-2) in this study was identified as a Glycine max nodule autoregulation receptor-like protein kinase precursor, previously identified by map-based cloning. These results demonstrate that cDNA-AFLP is a powerful technique to detect interesting genes without prior assumptions about the nature of the genes. The differentially expressed genes between Sinpaldalkong 2 and SS2-2 suggest that different signal transduction pathways for symbiosis may be involved in the two soybean genotypes.
authors.affiliation: Department of Plant Science, Seoul National University, Seoul, 151-921, Korea.
authors.forename: Puji
authors.initials: P
authors.lastname: Lestari
authors.forename: Kyujung
authors.initials: K
authors.lastname: VAN
authors.forename: Moon Young
authors.initials: MY
authors.lastname: Kim
authors.forename: Cheol Ho
authors.initials: CH
authors.lastname: Hwang
authors.forename: Byun-Woo
authors.initials: BW
authors.lastname: Lee
authors.forename: Suk-Ha
authors.initials: SH
authors.lastname: Lee