Molecular cloning and characterization of patellin1, a novel sec14-related protein, from zucchini (Cucurbita pepo)

SummaryA full-length patellin1 (PATL1) cDNA was cloned and characterized from zucchini (Cucurbita pepo). PATL1, originally discovered in the higher plant Arabidopsis thaliana, is a plant Sec14-related protein that localizes to the cell plate during the late stages of cytokinesis. PATL1 is related in sequence to other eukaryotic proteins involved in membrane trafficking and is thought to participate in vesicle trafficking events associated with cell plate maturation. The zucchini PATL1 (CpPATL1) cDNA predicts a 605 amino acid protein which consists of an acidic N-terminal domain (pI=4.2) followed by a Sec14 lipid-binding domain and a C-terminal Golgi dynamics domain (GOLD). The predicted CpPATL1 protein sequence shows a high degree of similarity to Arabidopsis PATL1, especially in the Sec14 (84%) and GOLD domains (87%). A phylogenetic analysis of all available full-length PATL sequences revealed that the PATLs belong to four distinct clades; CpPATL1 is a member of the PATL1/2 clade. RT-PCR analysis showed that the CpPATL1 gene is highly expressed throughout the plant. The domain structure, as well as biochemical fractionation studies, which demonstrated that CpPATL1 is a peripheral membrane protein, support a role in membrane trafficking events.