Abstract The Caenorhabditis elegans gene gld-1 is essential for oocyte development; in (null) hermaphrodites, a tumor forms where oogenesis would normally occur. We use genetic epistasis analysis to demonstrate that formation dependent on the sexual fate of germline. When germline sex determination pathway set female mode (terminal fem/fog genes inactive), germ cells exit meiotic prophase and proliferate form tumor, but when male mode, they develop into sperm. conclude phenotype cell-type...

The C. elegans germline provides an excellent model for analyzing the regulation of stem cell activity and decision to differentiate undergo meiotic development. distal end adult hermaphrodite contains proliferative zone, which includes a population mitotically cycling cells in S phase, followed by entry into prophase. fate is specified somatic tip (DTC) niche-germline GLP-1 Notch signaling through repression redundant GLD-1 GLD-2 pathways that promote meiosis. Here, we describe...

The glp-1 gene encodes a membrane protein required for inductive cell interactions during development of the nematode Caenorhabditis elegans. Here we report molecular characterization 15 loss-of-function (lf) mutations glp-1. Two nonsense appear to eliminate activity; both truncate in its extracellular domain and have strong phenotype. Twelve missense one in-frame deletion map sites within repeated motifs (10 epidermal growth factor [EGF]-like 3 LNG repeats extracellularly 6 cdc10/SWI6, or...

For proper sexual development of females, the Sex-lethal (Sxl) gene must be activated early in and remain on during rest life cycle. Conversely, males, Sxl functionally off through development. Here, we show that transcription unit spans a DNA segment greater than 20 kb encodes at least 10 distinct, but overlapping, RNA species. These RNAs range size from 4.4 to 1.7 exhibit sex, stage, tissue specificity. Six RNAs, three female specific male specific, are first detected by midembryogenesis...

MET-2/SETDB1 and interactors LIN-65/ATF7IP ARLE-14/ARL14EP initiate heterochromatin formation during embryogenesis.

Many organisms have a mechanism for down regulating the expression of non-synapsed chromosomes and chromosomal regions during meiosis. This phenomenon is thought to function in genome defense. During early meiosis Caenorhabditis elegans, unpaired (e.g., male X chromosome) become enriched modification associated with heterochromatin transcriptional repression, dimethylation histone H3 on lysine 9 (H3K9me2). enrichment requires activity cellular RNA-directed RNA polymerase, EGO-1. Here we use...

There is little comprehensive information on the distribution of root systems among coexisting species, despite expected importance those distributions in determining composition and diversity plant communities. This gap knowledge particularly acute for grasslands, which possess large numbers species with morphologically indistinguishable roots. In this study we adapted a molecular method, fluorescent fragment length polymorphism, to identify fragments determine two grasslands Yellowstone...

Abstract The distal tip cell (DTC) regulates the proliferation or differentiation choice in Caenorhabditis elegans germline by an inductive mechanism. Cell signaling requires a putative receptor germline, encoded b y glp-1 gene, and signal from DTC, lag-2 gene. Both belong to multigene gene families whose members are essential for during development of various tissues insects vertebrates as well C. elegans. Relatively little is known about how these pathways regulate fate choice. To identify...

Early in this century it was discovered that a rather small change (50%) the relative number of X chromosomes Drosophila melanogaster is responsible for one more striking examples differential gene expression observed higher eukaryotes. This classical illustration fundamental puzzle developmental biology involves fruit fly sexual differentiation. Diploid cells with two (X chromosomes:sets autosomes = 1) differentiate as female, whereas diploid only chromosome (X:A 0.5) male (Bridges 1925).

Caenorhabditis elegans EGO-1, a putative cellular RNA-directed RNA polymerase, promotes several aspects of germline development, including proliferation, meiosis, and gametogenesis, ensures robust response to interference. In C. elegans, GLP-1/Notch signaling from the somatic gonad maintains population proliferating germ cells, while entry cells into meiosis is triggered by GLD-1 GLD-2 pathways. GLP-1 prevents entering inhibiting activity. We originally identified ego-1 gene on basis genetic...

Abstract In the Caenorhabditis elegans germline, proliferation is induced by Notch-type signaling. Entry of germ cells into meiosis triggered activity GLD-1 and GLD-2 pathways, which function redundantly to promote and/or inhibit proliferation. Activation germline receptor, GLP-1, ultimately inhibits activities pathways. We previously identified several ego (enhancer glp-1) genes that interact genetically with GLP-1 signaling pathway. Here, we show atx-2 an gene. Our data suggest ATX-2 not a...

Abstract The glp-1 gene functions in two inductive cellular interactions and development of the embryonic hypodermis C. elegans. We have isolated six mutations as recessive suppressors temperature-sensitive (ts) glp-1. By mapping complementation tests, we found that these are known dumpy (dpy) genes; dpy genes required for normal body shape. Based on this result, asked whether previously screens mutants defective shape could also suppress (ts). From learned unselected eight elegans...

Evaluating how belowground processes contribute to plant community dynamics is hampered by limited information on the spatial structure of root communities at scale that plants interact belowground. In this study, roots were mapped nearest one mm and molecularly identified species vertical (0-15 cm deep) surfaces soil blocks excavated from dry mesic grasslands in Yellowstone National Park (YNP) examine relationships among interact. Our results indicated average interspecific - distances for...

Abstract microRNAs are frequently modified by addition of untemplated nucleotides to the 3′ end, but role this tailing is often unclear. Here we characterize prevalence and functional consequences microRNA in vivo, using Caenorhabditis elegans. MicroRNA C. elegans consists mostly mono-uridylation mature species, with rarer mono-adenylation which likely added precursors. Through a targeted RNAi screen, discover that TUT4/TUT7 gene family member CID-1/CDE-1/PUP-1 required for uridylation,...

Histone modifications regulate gene expression and chromosomal events, yet how histone-modifying enzymes are targeted is poorly understood. Here we report that a conserved DNA repair protein, SMRC-1, associates with MET-2, the C. elegans histone methyltransferase responsible for H3K9me1 me2 deposition. We used molecular, genetic, biochemical methods to investigate biological role of SMRC-1 explore its relationship MET-2. like mammalian ortholog SMARCAL1, provides protection from replication...

Members of the Notch gene family are thought to mediate inductive cell-cell interactions during develop ment a wide variety vertebrates and invertebrates. These genes encode transmembrane proteins that appear act as receptors contain three repeated sequence motifs. Two these motifs (an epidermal growth factor like cdc10/SW16/ankyrin sequence) have been found in large number unrelated proteins, while third motif (a lin-12/Notch/glp-1 is unique family. We present phylogenetic analysis 17...

Abstract The glp-1 gene is essential for two cell interactions that control fate in Caenorhabditis elegans: induction of anterior pharynx the embryo and mitotic proliferation germ line. To identify other genes involved these interactions, we have isolated suppressors temperature sensitive alleles glp-1. Each 14 recessive rescues both embryonic germline glp-1(ts) defects. These are extragenic define a set six designated sog, suppressor Suppression only obvious phenotype associated with sog...