title: 3' UTR signals necessary for expression of the Plasmodium gallinaceum ookinete protein, Pgs28, share similarities with those of yeast and plants.
abstract: During metazoan development, 3' UTR signals mediate the time and place of gene expression. For protozoan Plasmodium parasites, the formation of ookinetes from gametes in the mosquito midgut is an analogous developmental process. Previous studies of the 3' UTR signals necessary for expression of Pgs28, the major surface protein of Plasmodium gallinaceum ookinetes, suggested that a 3' UTR T-rich region and DNA sequences containing an ATTAAA eukaryotic polyadenylation consensus motif were necessary for its expression. During metazoan development, U-rich elements may function in conjunction with eukaryotic polyadenylation consensus signals to mediate developmental protein expression. To define whether the putative Plasmodium elements were mediators of Pgs28 expression mutations of these nucleotide sequences were made in plasmid constructs. The effect of the mutations on Pgs28 expression was tested by the transient gene transfection of sexual stage P. gallinaceum parasites. These studies reveal that two different mutations of the ATTAAA motif, which alter gene expression in higher eukaryotes and yeast, do not alter the expression of Pgs28. However, the U-rich element, adjacent nucleotides UUUACAAAAUUGUUUUAACU and downstream nucleotides UAUAUAAAA are able to mediate expression to varying degrees. The organization and overlapping function of these elements appears to more closely resemble that of yeasts or plants than those of metazoans.
authors.affiliation: Department of Medicine, Division of International Medicine and Infectious Diseases, Weill Medical College of Cornell University, 1300 York Avenue, Room A421, New York, NY 10021, USA.
authors.forename: Helen
authors.initials: H
authors.lastname: Cann
authors.forename: Silvia V
authors.initials: SV
authors.lastname: Brown
authors.forename: Raphael M
authors.initials: RM
authors.lastname: Oguariri
authors.forename: Linnie M
authors.initials: LM
authors.lastname: Golightly
mesh_terms: D020413:3' Untranslated Regions; D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics*; D001483:Base Sequence; D016054:DNA, Protozoan / Q000235:genetics; D005786:Gene Expression Regulation; D017125:Genes, Protozoan; D008969:Molecular Sequence Data; D010944:Plants / Q000235:genetics / Q000378:metabolism; D010964:Plasmodium gallinaceum / Q000235:genetics* / Q000378:metabolism; D015800:Protozoan Proteins / Q000235:genetics*; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016053:RNA, Protozoan / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity
chemical_list: D020413:3' Untranslated Regions; D000953:Antigens, Protozoan; D016054:DNA, Protozoan; C079421:Pgs28 protein, Plasmodium gallinaceum; D015800:Protozoan Proteins; D012333:RNA, Messenger; D016053:RNA, Protozoan