Inactivation of the flax rust resistance gene M associated with loss of a repeated unit within the leucine-rich repeat coding region.
The M rust resistance gene from flax was cloned after two separate approaches, an analysis of spontaneous M mutants with an L6 gene-derived DNA probe and tagging with the maize transposon Activator, independently identified the same gene. The gene encodes a protein of the nucleotide binding site leucine-rich repeat class and is related (86% nucleotide identity) to the unlinked L6 rust resistance gene. In contrast to the L locus, which contains a single gene with multiple alleles, approximately 15 related genes occur at the complex M locus, with only one encoding the M resistance specificity. The M protein contains two direct repeats of 147 and 149 amino acids in the C-terminal part of the leucine-rich region. Three mutant alleles of M encoding a product containing a single repeat unit of 154 amino acids were isolated. The mutant DNA sequences probably occurred by unequal intragenic exchange in the coding region of the repeats. The recombinant alleles lost M resistance and gained no detectable new resistance specificity.
Anderson
P A
PA
Commonwealth Scientific and Industrial Research Organization, Division of Plant Industry, Canberra, Australia.
Lawrence
G J
GJ
Morrish
B C
BC
Ayliffe
M A
MA
Finnegan
E J
EJ
Ellis
J G
JG
D000595:Amino Acid Sequence; D018744:DNA, Plant; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D007930:Leucine / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics*; D010944:Plants / Q000235:genetics*; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid
D018744:DNA, Plant; C095731:L6 protein, Linum usitatissimum; D010940:Plant Proteins; D007930:Leucine