Two WD-repeat genes from cotton are functional homologues of the Arabidopsis thaliana TRANSPARENT TESTA GLABRA1 (TTG1) gene.
Cotton fibres are single, highly elongated cells derived from the outer epidermis of ovules, and are developmentally similar to the trichomes of Arabidopsis thaliana. To identify genes involved in the molecular control of cotton fibre initiation, we isolated four putative homologues of the Arabidopsis trichome-associated gene TRANSPARENT TESTA GLABRA1 (TTG1). All four WD-repeat genes are derived from the ancestral D diploid genome of tetraploid cotton and are expressed in many tissues throughout the plant, including ovules and growing fibres. Two of the cotton genes were able to restore trichome formation in ttg1 mutant Arabidopsis plants. Both these genes also complemented the anthocyanin defect in a white-flowered Matthiola incana ttg1 mutant. These results demonstrate parallels in differentiation between trichomes in cotton and Arabidopsis, and indicate that these cotton genes may be functional homologues of AtTTG1.
Humphries
John A
JA
School of Molecular and Biomedical Science, The University of Adelaide, Adelaide SA 5005, Australia.
Walker
Amanda R
AR
Timmis
Jeremy N
JN
Orford
Sharon J
SJ
D000595:Amino Acid Sequence; D000872:Anthocyanins / Q000096:biosynthesis; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000235:genetics*; D019607:Brassicaceae / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D035264:Flowers / Q000235:genetics / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D003368:Gossypium / Q000235:genetics* / Q000254:growth & development; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified; D020033:Protein Isoforms / Q000235:genetics; D020449:Repetitive Sequences, Amino Acid / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D000872:Anthocyanins; D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D018744:DNA, Plant; D010940:Plant Proteins; D020033:Protein Isoforms; C121067:TTG1 protein, Arabidopsis