TY - JOUR

T1 - Cloning and expression analysis of candidate genes involved in wax deposition along the growing barley (Hordeum vulgare) leaf

AU - Richardson, Andrew

AU - Boscari, Alexandre

AU - Schreiber, Lukas

AU - Kerstiens, Gerhard

AU - Jarvis, Mike

AU - Herzyk, Pawel

AU - Fricke, Wieland

PY - 2007/11

Y1 - 2007/11

N2 - The aim of the present study was to isolate clones of genes which are likely to be involved in wax deposition on barley leaves. Of particular interest were those genes which encode proteins that take part in the synthesis and further modification of very long chain fatty acids (VLCFAs), the precursors of waxes. Previously, it had been shown that wax deposition commences within a spatially well-defined developmental zone along the growing barley leaf (Richardson et al. in Planta 222:472–483, 2005). In the present study, a barley microarray approach was used to screen for candidate contig-sequences (www.barleybase.org) that are expressed particularly in those leaf zones where wax deposition occurs and which are expressed specifically within the epidermis, the site of wax synthesis. Candidate contigs were used to screen an established in-house cDNA library of barley. Six full-length coding sequences clones were isolated. Based on sequence homologies, three clones were related to Arabidopsis CER6/CUT1, and these clones were termed HvCUT1;1, HvCUT1;2 and HvCUT1;3. A fourth clone, which was related to Arabidopsis Fiddlehead (FDH), was termed HvFDH1;1. These clones are likely to be involved in synthesis of VLCFAs. A fifth and sixth clone were related to Arabidopsis CER1, and were termed HvCER1;1 and HvCER1;2. These clones are likely to be involved in the decarbonylation pathway of VLCFAs. Semi-quantitative RT-PCR confirmed microarray expression data. In addition, expression analyses at 10-mm resolution along the blade suggest that HvCUT1;1 (and possibly HvCUT1;2) and HvCER1;1 are involved in commencement of wax deposition during barley leaf epidermal cell development. Electronic supplementary material The online version of this article (doi:10.1007/s00425-007-0585-0) contains supplementary material, which is available to authorized users.

AB - The aim of the present study was to isolate clones of genes which are likely to be involved in wax deposition on barley leaves. Of particular interest were those genes which encode proteins that take part in the synthesis and further modification of very long chain fatty acids (VLCFAs), the precursors of waxes. Previously, it had been shown that wax deposition commences within a spatially well-defined developmental zone along the growing barley leaf (Richardson et al. in Planta 222:472–483, 2005). In the present study, a barley microarray approach was used to screen for candidate contig-sequences (www.barleybase.org) that are expressed particularly in those leaf zones where wax deposition occurs and which are expressed specifically within the epidermis, the site of wax synthesis. Candidate contigs were used to screen an established in-house cDNA library of barley. Six full-length coding sequences clones were isolated. Based on sequence homologies, three clones were related to Arabidopsis CER6/CUT1, and these clones were termed HvCUT1;1, HvCUT1;2 and HvCUT1;3. A fourth clone, which was related to Arabidopsis Fiddlehead (FDH), was termed HvFDH1;1. These clones are likely to be involved in synthesis of VLCFAs. A fifth and sixth clone were related to Arabidopsis CER1, and were termed HvCER1;1 and HvCER1;2. These clones are likely to be involved in the decarbonylation pathway of VLCFAs. Semi-quantitative RT-PCR confirmed microarray expression data. In addition, expression analyses at 10-mm resolution along the blade suggest that HvCUT1;1 (and possibly HvCUT1;2) and HvCER1;1 are involved in commencement of wax deposition during barley leaf epidermal cell development. Electronic supplementary material The online version of this article (doi:10.1007/s00425-007-0585-0) contains supplementary material, which is available to authorized users.

KW - cuticle

KW - epidermal cell development

KW - Hordeum

KW - leaf growth

KW - microarray

KW - very long chain fatty acid elongation

KW - wax

KW - FATTY-ACID BIOSYNTHESIS

KW - CUTICULAR WAX

KW - COENZYME-A

KW - MOLECULAR CHARACTERIZATION

KW - MICROARRAY EXPERIMENTS

KW - CELL-DIFFERENTIATION

KW - ARABIDOPSIS-THALIANA

KW - ECERIFERUM MUTANTS

KW - POLLEN DEVELOPMENT

KW - BARRIER PROPERTIES

U2 - 10.1007/s00425-007-0585-0

DO - 10.1007/s00425-007-0585-0

M3 - Journal article

VL - 226

SP - 1459

EP - 1473

JO - Planta

JF - Planta

SN - 0032-0935

IS - 6

ER -