Identification of ARF and AUX/IAA Gene Families in Rafflesia cantleyi.

Rafflesia is a unique plant that produces the largest flowers in the world. It has a short blooming period of 6 to 7 days. Due to its rarity and limited accessibility, little is known about the growth and developmental process in the Rafflesia plant. In all plant species, auxin is the key hormone that is involved in growth and development. The auxin signal transduction involves members of the ARF transcription factor and AUX/IAA regulator families, which activate or inhibit the regulation of auxin response genes, thereby control the developmental process in plants. To gain a better understanding of molecular regulations in the Rafflesia plant development during flowering, members of the ARF and AUX/IAA gene families were identified from the transcriptome data of flower blooming stages in Rafflesia cantleyi. Based on Rafflesia unique transcripts (UTs) against the Arabidopsis TAIR database using BLASTX search, a total of nine UTs were identified as ARF transcription factors, while another seven UTs were identified as AUX/IAA regulators. These genes were found to be expressed in all three R. cantleyi flower stages i.e. days 1 (F1), 3 (F2), and 5 (F3). Gene expression analysis identified three genes that are differentially expressed in stage F1 vs. F2 i.e. IAA4 is upregulated while IAA8 and ARF3 are downregulated. These genes may be involved in the activation and/or inhibition of the auxin signal transduction pathway. Further analysis of these genes may unravel their function in the phenotypic development of the Rafflesia plant. [ABSTRACT FROM AUTHOR]

Copyright of AIP Conference Proceedings is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)