Characterization of leafy cotyledon1-like during embryogenesis in Theobroma cacao L.
Theobroma cacao L., an economically important crop for developing countries, can be experimentally propagated by somatic embryogenesis. Because of their potential roles in embryogenesis, a gene candidate strategy was initiated to find gene homologues of the members of the leafy cotyledon family of transcription factors. A homologue of the leafy cotyledon1-like gene, that encodes the HAP 3 subunit of the CCAAT box-binding factor, was found in the cocoa genome (TcL1L). The translated peptide shared a high amino acid sequence identity with the homologous genes of Arabidopsis thaliana, Phaseolus coccineus and Helianthus annuus. TcL1L transcripts mainly accumulated in young and immature zygotic embryos, and, to a lesser extent, in young and immature somatic embryos. In situ hybridization specified the localization of the transcripts as being mainly in embryonic cells of young embryos, the meristematic cells of the shoot and root apex of immature embryos, and in the protoderm and epidermis of young and immature embryos, either zygotic or somatic. Non-embryogenic explants did not show TcL1L expression. Ectopic expression of the TcL1L gene could partially rescue the Arabidopsis lec1 mutant phenotype, suggesting a similarity of function in zygotic embryogenesis.
Alemanno
Laurence
L
Centre de Coopération Internationale en Recherche Agronomique pour le Développement, CIRAD, UMR DAP, TA A-96/03, Avenue Agropolis, 34398 Montpellier Cedex 5, France.
Devic
Martine
M
Niemenak
Nicolas
N
Sanier
Christine
C
Guilleminot
Jocelyne
J
Rio
Mariannick
M
Verdeil
Jean-Luc
JL
Montoro
Pascal
P
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D015139:Blotting, Southern; D002099:Cacao / Q000196:embryology* / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D014170:Transformation, Genetic
D010940:Plant Proteins