Molecular characterisation of two homoeologous elicitor-responsive lipin genes in cotton
- 297 Downloads
The identification and molecular characterisation of two lipin-like gene copies (GhLIPN) in cotton, Gossypium hirsutum, an allotetraploid derived from two progenitor diploid Gossypium species, is described. Sequence analyses of the GhLIPN copies, designated GhLIPN-1 and -2, revealed that they contain 11 exons, separated by ten introns. They each have a 2,643 bp open reading frame that encodes 880 aa proteins, and share a 97.7 and 95.5 % sequence similarity at the translated nucleotide and amino acid level, respectively. The GhLIPN genes have a distinct domain architecture consisting of an archetypical N-terminal lipin domain, followed by a haloacid dehalogenase (HAD) domain towards the C-terminus. A Southern blot did not distinguish between the two gene copies, which suggests that they may be homoeologs rather than paralogs. GhLIPN-2 is more similar to a homoeologous sequence from G. raimondii, representing the ancestral D-genome, compared to GhLIPN-1 that matches G. herbaceum and that represents the A-genome. Our data indicate that GhLIPN-1 and GhLIPN-2 are homoeologs that derive from the A- and the D-diploid genomes, respectively. The promoter sequences of GhLIPN-1 and -2 differ by 56 %, as a result of multiple indels. In silico analysis of the promoter regions revealed that both genes contain numerous putative defence-related and elicitor-responsive cis-elements that support a role for GhLIPN in defence responses. Relative quantification real-time PCR confirmed the up-regulation in response to a cell-wall-derived V. dahliae elicitor, which supported the association of GhLIPN with defence signalling. The results add a new dimension to the proposed roles of lipins in plants by suggesting that lipins may have a role in defence signalling.
KeywordsAllotetraploid Gossypium hirsutum Haloacid dehalogenase Homoeologs Lipin Phosphatidate phosphatase Verticillium dahliae
This work was supported by the South African National Research Foundation and the University of Johannesburg.
- Leon-Reyes A, Spoel S, de Lange E, Abe H, Kobayashi M, Tsuda S, Millenaar F, Welschen R, Ritsema T, Pieterse C (2009) Ethylene modulates the role of nonexpressor of pathogenesis-related genes1 in cross talk between salicylate and jasmonate signaling. Plant Physiol 149:1797–1809PubMedCrossRefGoogle Scholar
- Maleck K, Levine A, Eulgem T, Morgan A, Schmidt J, Lawton K, Dangl J, Dietrich R (2000) The transcriptome of Arabidopsis thaliana during systemic acquired resistance. Nature 26:403–410Google Scholar
- Sambrook J, Fritsch E, Maniatis T (1989) Molecular cloning: a laboratory manual. Cold Spring Harbour Laboratory Press, Cold Spring HarbourGoogle Scholar
- Udall J (2008) The Gossypium transcriptome. In: Paterson A (ed) Genetics and genomics of cotton. Springer, New York, pp 157–186Google Scholar
- Zwiegelaar M (2003) DDRT-PCR analysis of defence-related gene induction in cotton. RAU University, DissertationGoogle Scholar