title: Nodule-specific regulation of phosphatidylinositol transfer protein expression in Lotus japonicus.
abstract: Phosphatidylinositol transfer proteins (PITPs) modulate signal transduction pathways and membrane-trafficking functions in eukaryotes. Here, we describe the characterization of a gene family from Lotus japonicus that encodes a novel class of plant PITP-like proteins (LjPLPs) and that is regulated in an unusual nodule-specific manner. Members of this gene family were identified based on their nucleotide sequence homology with a previously described cDNA, LjNOD16, which encodes the L. japonicus late nodulin Nlj16. Nlj16 or highly related amino acid sequences are shown to constitute C-terminal domains of LjPLPs and are suggested to function as specific plasma membrane targeting modules. The expression patterns of one member of this gene family (LjPLP-IV) revealed that LjNOD16 mRNA synthesis in nodules is the result of the transcriptional activity of a nodule-specific promoter located in an intron of the LjPLP-IV gene. This intron-borne bidirectional promoter also generates nodule-specific antisense transcripts derived from the N-terminal PITP domain coding region of the LjPLP-IV gene. We propose that Nlj16 protein synthesis and LjPLP-IV antisense transcript generation are components of an elaborate mechanism designed to control LjPLP synthesis and/or functioning in nodules.
authors.affiliation: Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824, USA.
authors.forename: P
authors.initials: P
authors.lastname: Kapranov
authors.forename: S M
authors.initials: SM
authors.lastname: Routt
authors.forename: V A
authors.initials: VA
authors.lastname: Bankaitis
authors.forename: F J
authors.initials: FJ
authors.lastname: de Bruijn
authors.forename: K
authors.initials: K
authors.lastname: Szczyglowski
mesh_terms: D000595:Amino Acid Sequence; D016375:Antisense Elements (Genetics); D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics*; D002462:Cell Membrane / Q000378:metabolism; D018744:DNA, Plant; D015536:Down-Regulation; D007887:Fabaceae / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D007438:Introns; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism; D049294:Phospholipid Transfer Proteins; D010940:Plant Proteins / Q000235:genetics* / Q000502:physiology; D018517:Plant Roots; D010946:Plants, Medicinal; D011401:Promoter Regions, Genetic; D021381:Protein Transport; D012333:RNA, Messenger / Q000378:metabolism; D018749:RNA, Plant / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid
chemical_list: D016375:Antisense Elements (Genetics); D002352:Carrier Proteins; D018744:DNA, Plant; D008565:Membrane Proteins; C105761:Nlj16 protein, Lotus corniculatus; D018129:Phosphatidylinositol Phosphates; D049294:Phospholipid Transfer Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; C118289:SEC24 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins