Characterisation of six alpha-expansin genes in Gossypium hirsutum (upland cotton).
A genomic library screen and PCR-based strategies were employed to isolate six genes with sequence similarity to a cotton fibre-specific mRNA encoding an alpha-expansin. alpha-Expansins are cell wall proteins that facilitate cell wall extension by disruption of non-covalent bonds between wall components. The characterisation and expression analysis of these six novel genes ( GhExp1-GhExp6) is described. Four of them ( GhExp3- GhExp6) are expressed within multiple tissues of the cotton plant and two ( GhExp1 and GhExp2) give rise to transcripts that are specific to the developing cotton fibre. GhExp1 transcripts are highly abundant in the fibre, while transcripts for GhExp2 are detected at a low level. Cotton fibres are highly elongated cells of the ovule epidermis, and we envisage that GhExp1 may play an important role in cell wall extension during development.
Harmer
S E
SE
Department of Molecular Biosciences, Discipline of Genetics, The University of Adelaide, South Australia 5005, Australia.
Orford
S J
SJ
Timmis
J N
JN
D000595:Amino Acid Sequence; D005091:Exons / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D003368:Gossypium / Q000235:genetics*; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000737:chemistry / Q000235:genetics*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D014158:Transcription, Genetic
D010937:Plant Growth Regulators; D010940:Plant Proteins; C095825:expansin protein, plant