Sequencing and characterization of MADS-box gene in oil palm (Elaeis Guineensis)

• Main Author: Tan, Su Hui
• Format: Thesis
• Language: English; English
• Published: 2007
• Subjects: SB183-317 Field crops Including cereals, forage crops, grasses, legumes, root crops, sugar plants, textile plants, alkaloidal plants, medicinal plants
• Online Access: https://eprints.ums.edu.my/id/eprint/6456/1/24%20PAGES.pdf; https://eprints.ums.edu.my/id/eprint/6456/2/FULLTEXT.pdf; https://eprints.ums.edu.my/id/eprint/6456/

In plants, MADS-box genes family plays a key role in developments, including vegetative, floral and fruit development. This study focused on the MADS-box genes of oil palm, a crop of agricultural importance. In this plant, flowering is directly related to the yield of fruits. In this study, Elaeis guineensis MADS-box 1 (EMADS1) was isolated from the female flower of oil palm (Elaeis guineensis), using the 3' and 5' RACE (Rapid Amplification of CDNA Ends) strategies. The EMADS1 cDNA is 996 bp long, including a 5' UTR (75 bp), 3' UTR (192 bp) and a poly(A)+ tail. The EMADS1 cDNA contains a 729 bp coding region encoding 242 amino acids. The deduced amino acid sequence of EMADS1 indicated high homology with members of the MADS box family of transcription factors and contained a MADS domain of 60 amino acids (at position 76 - 255) and a K domain of 67 amino acids (at position 346 - 546), as well as I region of 30 amino acids (at position 256 - 345) and C-terminal of 86 amino acids (at position 547 - 804) included the stop codon. EMADS1 amino acids sequence contained the MEF2-like MADS domain and the K domain and thus suggested that EMADS1 is a Type II MADS-box gene. The EMADS1 protein sequence showed a high sequence similarities to AOM1 (80%) of asparagus, OM1 (80%) of orchid, LtAGL9 (78%) of Liriodendron tu/ipifera, PaAGL9.2 (83%) of avocado, VvMADS4 (79%) of grapevine, FBP2 (76%) of petunia, TM5 (82%) of tomato, SEP1 (63%), SEP2 (61%) and SEP3 (70%) of Arabidopsis, and EgAGL2-2 (100%), EgMADSB (98%), EgAGL2-1 (97%), EgAGL2-3 (92%), EgAGL2-5 (65%), and EgAGL2-4 (61%) of oil palm. Among the SEPALLATA MADS-box genes identified in Arabidopsis, EMADS1 protein sequence showed the highest similarity to SEP3 (AGL9). Phylogenetic tree analysis showed that EMADS1 fall into the AGL2 group. In AGL2 group, EMADS1 was subdivided to the AGL9 subgroup and at the same sub-branch with OM1 and AOM1 genes. Percentage of bootstrap values at EMADS1 and OM1 were 75 (neighbor-joining), 48.5 (maximum parsimony) and 36 (maximum likelihood).• EMADS1 protein sequence was most likely homologous to AGL2 group genes. RT-PCR analysis using total RNA isolated from immature male and female flower buds, and seed embryo showed that the EMADS1 was ubiquitously expressed in the immature male and female flower buds. The expression pattern of EMADS1 in immature male and female flower buds was similar to EgAGL2-1, EgAGL2-2, EgAGL2-3, EgAGL2-4, EgAGL2-5, and EgMADS8 of oil palm. The EMADS1 transcript also accumulated in embryos of the developing seeds. These results suggested that EMADS1 may not only function in the important events controlling floral organ development in oil palm, but also in embryo development in seeds.