Identifikasi Molekular Kandidat Mutan Protein Heterotrimerik G Subunit α (Gα) dari Kedelai (Glycine max (L.) Merrill) Toleran Aluminium Kultivar Slamet

Abstract

Heterotrimeric G protein α Subunit (Gα) is predicted to play an important role in soybean tolerance mechanism to aluminum stress and low pH. Aluminum stress inhibits soybean growth and induces root damage. The expression of Gα gene is induced under Al stress condition. The objective of this research was to identify six lines of Gα mutant candidates using molecular technique. Six soybean mutant lines were planted and selected based on representative characters of Gα mutant, which were dwarf phenotypes and stomatal closure during daylight. Identification of Gα gene on mutant candidates was carried out through PCR method by using genomic DNA as a template from mutant and wild type cv. Slamet as the control plant. Three mutant candidates (338/3S1.174/12/1/4, 103/3S3.103/8/5/1/4, and 344/3S1.196/14/1/8) were chosen from all the selected lines to identify Gα gene. Before gene identification, a proper primer choosed by combined a designed primer from cDNA of Gα gene from cv. Slamet and Gα genomic of rice. A numbers of primers were generated from rice Gα genomic and soybean Gα cDNA sequences. Three primers were selected based on the ability of the primer to amplify soybean Gα cDNA cv. Slamet. Only primers that could amplify Gα cDNA used in molecular identification. Among those selected primer, three pairs of primers were successfully amplifying Gα cDNA. Only the primers combination U3-L4 could identify Gα mutant in line number 338/3S1.174/12/1/4 and 103/3S3.103/8/5/1/4, but not in number 344/3S1.196/14/1/8.