A class I KNOX gene from the palm species Elaeis guineensis (Arecaceae) is associated with meristem function and a distinct mode of leaf dissection.
Class I Knotted-like homeobox (KNOX) transcription factors are important regulators of shoot apical meristem function and leaf morphology by their contribution to dissected leaf development. Palms are of particular interest as they produce dissected leaves generated by a distinct mechanism compared with eudicots. The question addressed here was whether class I KNOX genes might be involved in meristem function and leaf dissection in palms. Here, we characterized the EgKNOX1 gene from oil palm (Elaeis guineensis, Arecaceae) and compared it with available sequences from other plant species using phylogenetic analysis. Gene expression pattern was investigated using reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. Functional analysis was carried out by ectopic expression in Arabidopsis and rice. EgKNOX1 was orthologous to STM from Arabidopsis and to OSH1 from rice. It was expressed in the central zone of both vegetative and reproductive meristems. During leaf development, its expression was associated with plications from which the leaflets originate. Different modes of leaf dissection are seen to involve a similar class of genes to control meristematic activities, which govern the production of dissected morphologies.
Jouannic
Stefan
S
IRD/CIRAD Palm Group, UMR 1098, Centre IRD Montpellier, 911 avenue Agropolis, 34394 Montpellier cedex 5, France.
Collin
Myriam
M
IRD/CIRAD Palm Group, UMR 1098, Centre IRD Montpellier, 911 avenue Agropolis, 34394 Montpellier cedex 5, France.
Vidal
Benjamin
B
IRD/CIRAD Palm Group, UMR 1098, Centre IRD Montpellier, 911 avenue Agropolis, 34394 Montpellier cedex 5, France.
Verdeil
Jean-Luc
JL
Plateau d'Histocytologie et d'Imagerie Cellulaire Végétale, IFR 127, TA/40/02, CIRAD, Avenue Agropolis, F-34398 Montpellier cedex 5, France.
Tregear
James W
JW
IRD/CIRAD Palm Group, UMR 1098, Centre IRD Montpellier, 911 avenue Agropolis, 34394 Montpellier cedex 5, France.
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D028023:Arecaceae / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000235:genetics*; D018519:Meristem / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics*; D010940:Plant Proteins / Q000235:genetics*
D018398:Homeodomain Proteins; D010940:Plant Proteins