title: BLIMP-1/BLMP-1 and Metastasis-Associated Protein Regulate Stress Resistant Development in Caenorhabditis elegans.
abstract: Environmental stress triggers multilevel adaptations in animal development that depend in part on epigenetic mechanisms. In response to harsh environmental conditions and pheromone signals, Caenorhabditis elegans larvae become the highly stress-resistant and long-lived dauer. Despite extensive studies of dauer formation pathways that integrate specific environmental cues and appear to depend on transcriptional reprogramming, the role of epigenetic regulation in dauer development has remained unclear. Here we report that BLMP-1, the BLIMP-1 ortholog, regulates dauer formation via epigenetic pathways; in the absence of TGF-β signaling (in daf-7 mutants), lack of blmp-1 caused lethality. Using this phenotype, we screened 283 epigenetic factors, and identified lin-40, a homolog of metastasis-associate protein 1 (MTA1) as an interactor of BLMP-1 The interaction between LIN-40 and BLMP-1 is conserved because mammalian homologs for both MTA1 and BLIMP-1 could also interact. From microarray studies, we identified several downstream target genes of blmp-1: npr-3, nhr-23, ptr-4, and sams-1 Among them S-adenosyl methionine synthase (SAMS-1), is the key enzyme for production of SAM used in histone methylation. Indeed, blmp-1 is necessary for controlling histone methylation level in daf-7 mutants, suggesting BLMP-1 regulates the expression of SAMS-1, which in turn may regulate histone methylation and dauer formation. Our results reveal a new interaction between BLMP-1/BLIMP-1 and LIN-40/MTA1, as well as potential epigenetic downstream pathways, whereby these proteins cooperate to regulate stress-specific developmental adaptations.
authors.affiliation: Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia 23298 Moonjung.Hyun@vcuhealth.org.
authors.forename: Moonjung
authors.identifier: 0000-0003-3320-9815
authors.initials: M
authors.lastname: Hyun
authors.affiliation: Department of Biological Sciences, Inha University, Incheon, 402-751, South Korea.
authors.forename: Jeongho
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Pathology, Virginia Commonwealth University, Richmond, Virginia 23298.
authors.forename: Catherine
authors.initials: C
authors.lastname: Dumur
authors.affiliation: Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853.
authors.forename: Frank C
authors.initials: FC
authors.lastname: Schroeder
authors.affiliation: Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia 23298.
authors.forename: Young-Jai
authors.initials: YJ
authors.lastname: You
mesh_terms: D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics*; D044127:Epigenesis, Genetic; D018507:Gene Expression Regulation, Developmental; D007814:Larva / Q000235:genetics; D009154:Mutation; D012097:Repressor Proteins; D015398:Signal Transduction; D013312:Stress, Physiological / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000235:genetics* / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; C102095:DAF-7 protein, C elegans; C000619232:LIN-40 protein, C elegans; D012097:Repressor Proteins; D014157:Transcription Factors; D016212:Transforming Growth Factor beta; C000600050:blmp-1 protein, C elegans; D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase
keywords: BLMP-1; TGF-β; dauer; epigenetics; stress resistant development