MACDONALD WW (1963) Ann Trop Med Parasitol "A PRELIMINARY CROSS-OVER VALUE BETWEEN THE GENE FM (FILARIAL SUSCEPTIBILITY, BRUGIA MALAYI) AND THE SEX LOCUS IN AEDES AEGYPTI."

MACDONALD WW

[Ann Trop Med Parasitol, 1963]

MACDONALD WW et al. (1965) Ann Trop Med Parasitol "THE INFLUENCE OF THE GENE FM (FILARIAL SUSCEPTIBILITY, BRUGIA MALAYI) ON THE SUSCEPTIBILITY OF AEDES AEGYPTI TO SEVEN STRAINS OF BRUGIA, WUCHERERIA AND DIROFILARIA."

MACDONALD WW, RAMACHANDRAN CP

[Ann Trop Med Parasitol, 1965]

Kato Y et al. (2002) J Biol Chem "Determinants of ligand specificity in groups I and IV WW domains as studied by surface plasmon resonance and model building."

Kato Y, Ito M, Tanokura M, Kawai K, Nagata K

[J Biol Chem, 2002]

WW domains are universal protein modules for binding Pro-rich ligands. They are classified into four groups according to their binding specificity. Arg-14 and Arg-17, on the WW domain of Pin1, are thought to be important for the binding of Group IV ligands that have (Ser(P)/Thr(P))-Pro sequences. We have applied surface plasmon resonance to determine the ligand specificity of several WW domains containing Arg-14. Among these WW domains, Rsp5.2 and mNedd4.3 bound only to the Group I ligand containing Pro-Pro-Xaa-Tyr with K(D) values of 11 and 55 microm, respectively. The WW domains of hPin1, Caenorhabditis elegans Pin1 homologue (Y110), PinA, and SspI bound to Group IV ligands with K(D) values ranging from 22 to 700 microm. PinA and SspI do not have Arg-17, unlike Pin1 and Y110. The modeled structures of the WW domains of PinA and SspI revealed that the structure and the network of hydrogen bonds of Loop I, which are also formed in Pin1 and Y110, are conserved. We propose that this configuration of Loop I (referred to as the "p patch") is necessary for binding Group IV ligands and that it can be used to predict the specificity and functions of other WW domains.

Wright GM et al. (2019) Nucleic Acids Res "The nucleosome position-encoding WW/SS sequence pattern is depleted in mammalian genes relative to other eukaryotes."

Cui F, Wright GM

[Nucleic Acids Res, 2019]

Nucleosomal DNA sequences generally follow a well-known pattern with 10-bp periodic WW (where W is A or T) dinucleotides that oscillate in phase with each other and out of phase with SS (where S is G or C) dinucleotides. However, nucleosomes with other DNA patterns have not been systematically analyzed. Here, we focus on an opposite pattern, namely anti-WW/SS pattern, in which WW dinucleotides preferentially occur at DNA sites that bend into major grooves and SS (where S is G or C) dinucleotides are often found at sites that bend into minor grooves. Nucleosomes with the anti-WW/SS pattern are widespread and exhibit a species- and context-specific distribution in eukaryotic genomes. Unlike non-mammals (yeast, nematode and fly), there is a positive correlation between the enrichment of anti-WW/SS nucleosomes and RNA Pol II transcriptional levels in mammals (mouse and human). Interestingly, such enrichment is not due to underlying DNA sequence. In addition, chromatin remodeling complexes have an impact on the abundance but not on the distribution of anti-WW/SS nucleosomes in yeast. Our data reveal distinct roles of cis- and trans-acting factors in the rotational positioning of nucleosomes between non-mammals and mammals. Implications of the anti-WW/SS sequence pattern for RNA Pol II transcription are discussed.

Serizay J et al. (2020) Genome Res "Distinctive regulatory architectures of germline-active and somatic genes in C. elegans."

Dong Y, Serizay J, Chesney M, Cerrato C, Ahringer J, Janes J

[Genome Res, 2020]

RNA profiling has provided increasingly detailed knowledge of gene expression patterns, yet the different regulatory architectures that drive them are not well understood. To address this, we profiled and compared transcriptional and regulatory element activities across five tissues of <i>C. elegans</i>, covering ~90% of cells. We find that the majority of promoters and enhancers have tissue-specific accessibility, and we discover regulatory grammars associated with ubiquitous, germline and somatic tissue-specific gene expression patterns. In addition, we find that germline-active and soma-specific promoters have distinct features. Germline-active promoters have well positioned +1 and -1 nucleosomes associated with a periodic 10-bp WW signal (W = A/T). Somatic tissue-specific promoters lack positioned nucleosomes and this signal, have wide nucleosome depleted regions, and are more enriched for core promoter elements, which differ between tissues. We observe the 10-bp periodic WW signal at ubiquitous promoters in other animals suggesting it is an ancient conserved signal. Our results demonstrate fundamental differences in regulatory architectures of germline and somatic tissue-specific genes, uncover regulatory rules for generating diverse gene expression patterns, and provide a tissue-specific resource for future studies.

Courbard JR et al. (2002) J Biol Chem "Interaction between two ubiquitin-protein isopeptide ligases of different classes, CBLC and AIP4/ITCH."

Birnbaum D, Fiore F, Borg JP, Ollendorff V, Courbard JR, Adelaide J

[J Biol Chem, 2002]

In metazoans, CBL proteins are RING finger type ubiquitin-protein isopeptide (E3) ligases involved in the down-regulation of epidermal growth factor tyrosine kinase receptors (EGFR). Among the three CBL proteins described in humans, CBLC (CBL3) remains poorly studied. By screening in parallel a human and a Caenorhabditis elegans library using the two-hybrid procedure in yeast, we found a novel interaction between Hsa-CBLC and Hsa-AIP4 or its C. elegans counterpart Cel-WWP1. Hsa-AIP4 and Cel-WWP1 are also ubiquitin E3 ligases. They contain a HECT (homologous to E6-AP C terminus) catalytic domain and four WW domains known to bind proline-rich regions. We confirmed the interaction between Hsa-CBLC and Hsa-AIP4 by a combination of glutathione S-transferase pull-down, co-immunoprecipitation, and colocalization experiments. We show that these two E3 ligases are involved in EGFR signaling because both become phosphorylated on tyrosine following epidermal growth factor stimulation. In addition, we observed that CBLC increases the ubiquitination of EGFR, and that coexpressing the WW domains of AIP4 exerts a dominant negative effect on EGFR ubiquitination. Finally, coexpressing CBLC and AIP4 induces a down-regulation of EGFR signaling. In conclusion, our data demonstrate that two E3 ligases of different classes can interact and cooperate to down-regulate EGFR signaling.

Ung, Hailey M. et al. (2020) MicroPubl Biol

Ung, Hailey M., Kikis, Elise A., Hall, Rhodes H.

[MicroPubl Biol, 2020]

Huntingtons disease (HD) is an autosomal dominant monogenic neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the gene encoding the protein huntingtin (Htt) (MacDonald et al., 1993). The resultant disease-associated Htt protein harbors a polyglutamine (polyQ) repeat that renders it metastable with respect to folding (Carrell and Lomas, 1997). Htt protein misfolding, characterized by the accumulation of misfolded protein aggregates and neurotoxicity, is first observed in mid- to late-life for most HD patients (Becher et al., 1998). The age-of-onset for HD is inversely proportional to CAG repeat length (Becher et al., 1998). Nonetheless, genetic variation between HD patients is attributed to slight differences in age-of-onset, even when repeat length is the same (Gusella and MacDonald, 2000). Thus, genetic background seems to be an important modifier of Htt protein aggregation and toxicity. We are interested in identifying genes/proteins that enhance or suppress the folding defect of human Htt.To model Htt toxic-gain-of-function in the genetically tractable Caenorhabditis elegans, we previously characterized transgenic animals expressing a YFP-tagged polyQ-expanded disease-associated fragment of human Htt in C. elegans body wall muscle cells (Lee et al., 2017). More specifically, the first 513 amino acids of the human Htt protein were fused to YFP for visualization. Two different polyQ tract lengths (Q15 and Q128) were utilized, resulting in the proteins Htt513(Q15)::YFP and Htt513(Q128)::YFP, corresponding to the strains EAK102 and EAK103, respectively (Lee et al., 2017). For simplicity, these proteins are referred to herein as Htt513(Q15) or Htt513(Q128). As reported, only Htt513(Q128), not Htt513(Q15), formed protein aggregates in body wall muscle cells (Lee et al., 2017), consistent with only longer polyQ tracts being associated with disease.Here, we describe the identification and characterization of genetic modifiers of Htt aggregation (mha). To this end, EAK103 animals expressing Htt513(Q128) were grown to the L4 larval stage and exposed to the alkylating agent ethyl methanesulfonate (EMS) at a final concentration of 50mM for 4hrs, according to established protocols (Brenner, 1974). In short, F1 individuals derived from the mutagenized parents were allowed to self-fertilize for one generation, yielding an F2 population, for the purpose of homozygosing recessive alleles and thereby uncovering mutant phenotypes. Screening of the F2 animals for those with increased or decreased aggregation was performed by eye with a fluorescent stereomicroscope.

Huang K et al. (2000) Gene "A HECT domain ubiquitin ligase closely related to the mammalian protein WWP1 is essential for Caenorhabditis elegans embryogenesis."

Mosser EA, Bresnick EH, Petcherski AG, Johnson KD, Kimble JE, Vandergon T, Huang K, Jenkins NA, Copeland NG

[Gene, 2000]

The highly conserved ubiquitin/proteasome pathway controls the degradation of many critical regulatory proteins. Proteins are posttranslationally conjugated to ubiquitin through a concerted set of reactions involving activating (E1), conjugating (E2), and ligase (E3) enzymes. Ubiquitination targets proteins for proteolysis via the proteasome and may regulate protein function independent of proteolysis. We describe the cloning and functional analysis of new members of the HECT domain family of E3 ubiquitin ligases. Murine Wwp1 encoded a broadly expressed protein containing a C2 domain, four WW domains, and a catalytic HECT domain. A Caenorhabditis elegans gene was cloned encoding a HECT domain protein (CeWWP1), which was highly homologous to murine and human WWP1. Disruption of CeWwp1 via RNA interference yielded an embryonic lethal phenotype, despite the presence of at least six additional C. elegans genes encoding HECT domain proteins. The embryonic lethality was characterized by grossly abnormal morphogenesis during late embryogenesis, despite normal proliferation early in embryogenesis. CeWWP1 must therefore have unique and nonredundant functions critical for embryogenesis.

Chen CS et al. (2010) PLoS One "WWP-1 is a novel modulator of the DAF-2 insulin-like signaling network involved in pore-forming toxin cellular defenses in Caenorhabditis elegans."

Chen HD, Aroian RV, Chen CS, Bellier A, Kao CY, Los FC, Yang YL

[PLoS One, 2010]

Pore-forming toxins (PFTs) are the single largest class of bacterial virulence factors. The DAF-2 insulin/insulin-like growth factor-1 signaling pathway, which regulates lifespan and stress resistance in Caenorhabditis elegans, is known to mutate to resistance to pathogenic bacteria. However, its role in responses against bacterial toxins and PFTs is as yet unexplored. Here we reveal that reduction of the DAF-2 insulin-like pathway confers the resistance of Caenorhabditis elegans to cytolitic crystal (Cry) PFTs produced by Bacillus thuringiensis. In contrast to the canonical DAF-2 insulin-like signaling pathway previously defined for aging and pathogenesis, the PFT response pathway diverges at 3-phosphoinositide-dependent kinase 1 (PDK-1) and appears to feed into a novel insulin-like pathway signal arm defined by the WW domain Protein 1 (WWP-1). In addition, we also find that WWP-1 not only plays an important role in the intrinsic cellular defense (INCED) against PFTs but also is involved in innate immunity against pathogenic bacteria Pseudomonas aeruginosa and in lifespan regulation. Taken together, our data suggest that WWP-1 and DAF-16 function in parallel within the fundamental DAF-2 insulin/IGF-1 signaling network to regulate fundamental cellular responses in C. elegans.

Holbert S et al. (2001) Proc Natl Acad Sci U S A "The Gln-Ala repeat transcriptional activator CA150 interacts with huntingtin: neuropathologic and genetic evidence for a role in Huntington's disease pathogenesis."

Holbert S, Ferrante RJ, Kiechle T, Hayden MR, Ross CA, Dausset J, Denghien I, Wellington C, Margolis RL, Neri C, Rosenblatt A

[Proc Natl Acad Sci U S A, 2001]

Huntington's disease (HD) is a neurodegenerative disease caused by polyglutamine expansion on the protein huntingtin (htt). Pathogenesis in HD appears to involve the formation of ubiquitinated neuronal intranuclear inclusions containing N-terminal mutated htt, abnormal protein interactions, and the aggregate sequestration of a variety of proteins (noticeably, transcription factors). To identify novel htt-interacting proteins in a simple model system, we used a yeast two-hybrid screen with a Caenorhabditis elegans activation domain library. We found a predicted WW domain protein (ZK1127.9) that interacts with N-terminal fragment of htt in two-hybrid tests. A human homologue of ZK1127.9 is CA150, a transcriptional coactivator with a N-terminal insertion that contains an imperfect (Gln-Ala) tract encoded by a polymorphic repeat DNA. CA150 interacted in vitro with full-length htt from lymphoblastoid cells. The expression of CA150, measured immunohistochemically, was markedly increased in human HD brain tissue compared with normal age-matched human brain tissue, and CA150 showed aggregate formation with partial colocalization to ubiquitin-positive aggregates. In 432 HD patients, the CA150 repeat length explains a small, but statistically significant, amount of the variability in the onset age. Our data suggest that abnormal expression of CA150, mediated by interaction with polyglutamine-expanded htt, may alter transcription and have a role in HD