GhLMM gene capable of substantially improving disease resistance of cotton and application thereof

Abstract

The invention discloses a GhLMM gene capable of substantially improving disease resistance of cotton and application thereof, belonging to the field of application of biotechnology. The invention provides the nucleotide sequences of the GhLMM gene in the genomic subgroup A and the genomic subgroup D of a standard genetic system of allotrtraploid upland cotton, the ORF sequences of the GhLMM gene, and amino acid sequences coded by the GhLMM gene. The GhLMM gene provided by the invention is acquired by subjecting a mutant gene of a cotton lesion-mimic mutant discovered for the first time to genetic analysis, fine mapping and map-based cloning. The GhLMM gene codes 5-aminolevulinic acid anhydrase (ALAD) and is an important gene in the process of metabolism of a tetrapyrrole compound in cotton; and inactivation of the gene leads to accumulation of a substrate, i.e., 5-aminolevulinic acid (ALA), so hydrogen peroxide and SA are produced and plant disease-resistance signals are activated. The GhLMM gene exerts dose effect on equilibrium between plant growth and disease resistance of plants. Optimal equilibrium between growth adaptability and disease resistance of plants can be realized by regulating the expression of the GhLMM gene.

Description

Technical field [0001] The invention relates to a cotton GhLMM gene, which encodes 5-aminolevulinic acid dehydratase (ALAD). Using the disease-like mutant Ghlmm discovered for the first time in upland cotton, the gene was obtained by map-based cloning technology. In the Ghlmm mutant, due to the GhLMM gene located in the D subgroup, a single nucleotide SNP mutation caused the coding region to terminate prematurely and lose its function. Disease resistance testing showed that the mutant's resistance to Verticillium wilt was significantly improved. The genomic sequence, the full-length ORF sequence and the encoded amino acid sequence of the gene were further obtained by PCR technology in the TM-1A subgroup and D subgroup of the genetic standard line of upland cotton. In tetraploid cotton, the gene contains four copies. The use of biotechnology to regulate the expression dose of the gene in tetraploid cotton can improve cotton disease resistance, which belongs to the field of biot...

AI Technical Summary

Problems solved by technology

Fine mapping and map-based cloning found that Ghlmm is due to a single nucleotide mutation in the Gh_D05G2237 coding region, which caused the premature termination of the translated polypeptide, resulting in a loss of function

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