novel mutation in TFL1 homolog affecting determinacy in cowpea (Vigna unguiculata)

• Published in: Molecular genetics and genomics : MGG Vol. 290; no. 1; pp. 55 - 65
• Main Authors: Dhanasekar, P, Reddy, K. S
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.02.2015; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: adenine; Amino Acid Sequence; Amino acids; Animal Genetics and Genomics; apical meristems; Arabidopsis; Biochemistry; bioinformatics; Biomedical and Life Sciences; conserved sequences; cowpeas; cytosine; exons; Fabaceae - anatomy & histology; Fabaceae - genetics; Fabaceae - growth & development; Families & family life; flowers; Flowers & plants; Gamma rays; Genes; Genomics; Human Genetics; ideotypes; Life Sciences; Meristem - growth & development; Microbial Genetics and Genomics; Molecular Sequence Data; mutants; Mutation; Mutation - genetics; Original Paper; parents; Phase transitions; Phylogeny; Plant Genetics and Genomics; Plant Proteins - chemistry; Plant Proteins - genetics; point mutation; Polymorphism, Single Nucleotide - genetics; Protein Stability; Proteins; Sequence Alignment; sequence analysis; Sequence Homology, Amino Acid; single nucleotide polymorphism; Vigna unguiculata; Determinate growth habit; Cowpea; Point mutation; Terminal flower
• ISSN: 1617-4615; 1617-4623
• DOI: 10.1007/s00438-014-0899-0

Mutations in the widely conserved Arabidopsis Terminal Flower 1 (TFL1) gene and its homologs have been demonstrated to result in determinacy across genera, the knowledge of which is lacking in cowpea. Understanding the molecular events leading to determinacy of apical meristems could hasten development of cowpea varieties with suitable ideotypes. Isolation and characterization of a novel mutation in cowpea TFL1 homolog (VuTFL1) affecting determinacy is reported here for the first time. Cowpea TFL1 homolog was amplified using primers designed based on conserved sequences in related genera and sequence variation was analysed in three gamma ray-induced determinate mutants, their indeterminate parent “EC394763” and two indeterminate varieties. The analyses of sequence variation exposed a novel SNP distinguishing the determinate mutants from the indeterminate types. The non-synonymous point mutation in exon 4 at position 1,176 resulted from transversion of cytosine (C) to adenine (A) leading to an amino acid change (Pro-136 to His) in determinate mutants. The effect of the mutation on protein function and stability was predicted to be detrimental using different bioinformatics/computational tools. The functionally significant novel substitution mutation is hypothesized to affect determinacy in the cowpea mutants. Development of suitable regeneration protocols in this hitherto recalcitrant crop and subsequent complementation assay in mutants or over-expressing assay in parents could decisively conclude the role of the SNP in regulating determinacy in these cowpea mutants.