Genetics of barley hooded suppression.
The molecular basis of the barley dominant Hooded (K) mutant is a duplication of 305 bp in intron IV of the homeobox gene Bkn3. A chemical mutagenesis screen was carried out to identify genetical factors that participate in Bkn3 intron-mediated gene regulation. Plants from recurrently mutagenized KK seeds were examined for the suppression of the hooded awn phenotype induced by the K allele and, in total, 41 suK (suppressor of K) recessive mutants were identified. Complementation tests established the existence of five suK loci, and alleles suKB-4, suKC-33, suKD-25, suKE-74, and suKF-76 were studied in detail. All K-suppressed mutants showed a short-awn phenotype. The suK loci have been mapped by bulked segregant analysis nested in a standard mapping procedure based on AFLP markers. K suppressor loci suKB, B, E, and F all map in a short interval of chromosome 7H, while the locus suKD is assigned to chromosome 5H. A complementation test between the four suK mutants mapping on chromosome 7H and the short-awn mutant lks2, located nearby, excluded the allelism between suK loci and lks2. The last experiment made clear that the short-awn phenotype of suK mutants is due to a specific dominant function of the K allele, a function that is independent from the control on hood formation. The suK loci are discussed as candidate participants in the regulation of Bkn3 expression.
Roig
Cristina
C
Max-Planck-Institut für Züchtungsforschung, 50829 Cologne, Germany.
Pozzi
Carlo
C
Santi
Luca
L
Müller
Judith
J
Wang
Yamei
Y
Stile
Maria Rosaria
MR
Rossini
Laura
L
Stanca
Michele
M
Salamini
Francesco
F
D000483:Alleles; D001665:Binding Sites; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D005786:Gene Expression Regulation; D018506:Gene Expression Regulation, Plant; D005801:Genes, Homeobox; D017343:Genes, Plant; D005816:Genetic Complementation Test; D008040:Genetic Linkage; D005838:Genotype; D018398:Homeodomain Proteins / Q000235:genetics*; D001467:Hordeum / Q000235:genetics* / Q000378:metabolism; D007438:Introns; D008957:Models, Genetic; D016296:Mutagenesis; D009154:Mutation; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic
D018398:Homeodomain Proteins; D010940:Plant Proteins