Eimeria maxima phosphatidylinositol 4-phosphate 5-kinase: locus sequencing, characterization, and cross-phylum comparison
- 122 Downloads
Phosphatidylinositol 4-phosphate 5-kinase (PIP5K) may play an important role in host-cell invasion by the Eimeria species, protozoan parasites which can cause severe intestinal disease in livestock. Here, we report the structural organization of the PIP5K gene in Eimeria maxima (Weybridge strain). Two E. maxima BAC clones carrying the E. maxima PIP5K (EmPIP5K) coding sequences were selected for shotgun sequencing, yielding a 9.1-kb genomic segment. The EmPIP5K coding region was initially identified using in silico gene-prediction approaches and subsequently confirmed by mapping rapid amplification of cDNA ends and RT-PCR-generated cDNA sequence to its genomic segment. The putative EmPIP5K gene was located at position 710-8036 nt on the complimentary strand and comprised of 23 exons. Alignment of the 1147 amino acid sequence with previously annotated PIP5K proteins from other Apicomplexa species detected three conserved motifs encompassing the kinase core domain, which has been shown by previous protein deletion studies to be necessary for PIP5K protein function. Phylogenetic analysis provided further evidence that the putative EmPIP5K protein is orthologous to that of other Apicomplexa. Subsequent comparative gene structure characterization revealed events of intron loss/gain throughout the evolution of the apicomplexan PIP5K gene. Further scrutiny of the genomic structure revealed a possible trend towards “intron gain” between two of the motif regions. Our findings offer preliminary insights into the structural variations that have occurred during the evolution of the PIP5K locus and may aid in understanding the functional role of this gene in the cellular biology of apicomplexan parasites.
KeywordsPlasmodium Species Coccidiosis Apicomplexan Parasite Intron Gain Eimeria Species
This project was supported by the Genomics and Molecular Biology Initiatives Programme of the Malaysia Genome Institute, Ministry of Science, Technology and Innovation Malaysia (Project No. 07-05-16-MGI-GMB10) and the Biotechnology and Biological Sciences Research Council, UK (BBSRC Grant BBE01089X1). The authors would like to acknowledge Dr Michael Quail for construction of the E. maxima BAC library and Karen Billington for construction of the SMART cDNA library. The authors would like to thank the Sanger Institute and the E. tenella Genome Consortium (http://www.sanger.ac.uk/Projects/E_tenella/consortium.shtml) for generation of the E. tenella sequencing data supported by the BBSRC and the Wellcome Trust.
- Katinka MD, Duprat S, Cornillot E, Metenier G, Thomarat F, Prensier G, Barbe V, Peyretaillade E, Brottier P, Wincker P, Delbac F, Alaoui HE, Peyret P, Saurin W, Gouy M, Weissenbach J, Vivares CP (2001) Genome sequence and gene compaction of the eukaryote parasite Encephalitozoon cuniculi. Nature 414:450–453CrossRefPubMedGoogle Scholar
- Ling KH, Rajandream MA, Rivailler P, Ivens A, Yap SJ, Madeira AMBN, Mungall K, Billington K, Yee WY, Bankier AT, Carroll F, Durham AM, Peters N, Loo SS, Mat-Isa MN, Novaes J, Quail M, Rosli R, Mariana NS, Sobreira TJP, Tivey A, Wai SF, White S, Wu X, Kerhornou A, Blake D, Mohamed R, Shirley M, Gruber A, Berriman M, Tomley F, Dear PH and Wan KL (2007b) Sequencing and analysis of chromosome 1 of Eimeria tenella reveals a unique segmental organization. Genome Research 17:311–319CrossRefPubMedGoogle Scholar
- Marchler-Bauer A, Anderson JB, Derbyshire MK, DeWeese-Scott C, Gonzales NR, Gwadz M, Hao L, He S, Hurwitz DI, Jackson JD, Ke Z, Krylov D, Lanczycki C, Liebert CA, Liu C, Lu F, Marchler GH, Mullokandov M, Song JS, Thanki N, Yamashita RA, Yin JJ, Zhang D, Bryant SH (2007) CDD: a conserved domain database for interactive domain family analysis. Nucleic Acids Res 35:D237–D240CrossRefPubMedGoogle Scholar
- Sambrook J, Russell DW (2001) Molecular cloning: a laboratory manual, 3rd edn. Cold Spring Harbor Laboratory Press, New YorkGoogle Scholar
- Shirley MW, Blake DP, White SE, Sheriff R, Smith AL (2004a) Integrating genetics and genomics to identify new leads for the control of Eimeria spp. Parasitol 128:S33–S42Google Scholar
- Tolias KF, Rameh LE, Ishihara H, Shibasaki Y, Chen J, Prestwich GD, Cantley LC, Carpenter CL (1998) Type I phosphatidylinositol-4-phosphate 5 kinases synthesizes the novel lipids phosphatidylinositol 3, 5-bisphosphate and phosphatidylinositol 5-phosphate. J Biol Chem 273:18040–18046CrossRefPubMedGoogle Scholar
- Zhu G, Marchewka MJ, Keithly JS (2000b) Cryptosporidium parvum appears to lack a plastid genome. Microbiol 146:315–321Google Scholar