RESEARCH ARTICLE

Journal of Oil Palm Research Vol. 26 (1) March 2014, p. 37-46

MOLECULAR CLONING AND REGULATION OF OIL PALM (E. guineensis Jacq.) PHYTOENE DESATURASE IN DEVELOPING MESOCARP TISSUES

O A Rasid*; W S Wan Nur Syuhada*; A Nor Hanin*; S S Masura* and G K A Parveez*

ABSTRACT

Oil palm is one of the richest natural sources of carotene and therefore it is an interesting target for genetic modification for high value carotenoid products. Phytoene desaturase (PDS) catalyses the formation of one of the double bonds during the conversion of phytoene into lycopene. Introduction of an additional copy of pds could potentially increase plant carotenoid content. Moreover, pds is considered as a potential target of bleaching herbicide action and as a determinant of geometric isomer states of carotenoids. This article describes the isolation of cDNA clones coding for pds from oil palm. In this work, we have successfully obtained a 865 bp fragment through reversed transcriptase PCR (RTPCR) using degenerate primers. The sequence information of this initial fragment was subsequently used to obtain full-length coding region of oil palm pds. The clone is moderately identical to other plant pds sequences at about 80% identity. Realtime PCR analysis was carried out to study the expression of the gene in the developing oil palm mesocarp tissues. Results indicate that the gene is highly regulated during the course of oil palm fruit development. The expression is relatively high in the 19-week mesocarp tissues as well as in mature leaves at about 1.97- and 2.42-fold, respectively compared to the calibrator. A moderate expression level of about 1.5-fold was observed in 5- and 15-week mesocarp and young leaf (spear leaf) tissues. The results suggest that oil palm pds is highly regulated during fruit development probably to meet the demand for growth or storage.

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* Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru
Bangi, 43000 Kajang, Selangor, Malaysia.
E-mail: omar@mpob.gov.my