A defining member of the new cysteine-cradle family is an aECM protein signalling skin damage in .

Apical extracellular matrices (aECMs) act as crucial barriers, and communicate with the epidermis to trigger protective responses following injury or infection. In , the skin aECM, the cuticle, is produced by the epidermis and is decorated with periodic circumferential furrows. We previously showed that mutants lacking cuticle furrows exhibit persistent immune activation (PIA).

Animal septins contain functional transmembrane domains.

Septins, a conserved family of filament-forming proteins, contribute to eukaryotic cell division, polarity, and membrane trafficking. Septins scaffold other proteins to cellular membranes, but it is not fully understood how septins associate with membranes. We identified and characterized an isoform of septin UNC-61 that was predicted to contain a transmembrane domain (TMD).

Meisosomes, folded membrane microdomains between the apical extracellular matrix and epidermis.

Apical extracellular matrices (aECMs) form a physical barrier to the environment. In , the epidermal aECM, the cuticle, is composed mainly of different types of collagen, associated in circumferential ridges separated by furrows. Here, we show that in mutants lacking furrows, the normal intimate connection between the epidermis and the cuticle is lost, specifically at the lateral epidermis, where, in contrast to the dorsal and ventral epidermis, there are no hemidesmosomes.

Human septins organize as octamer-based filaments and mediate actin-membrane anchoring in cells.

Septins are cytoskeletal proteins conserved from algae and protists to mammals. A unique feature of septins is their presence as heteromeric complexes that polymerize into filaments in solution and on lipid membranes. Although animal septins associate extensively with actin-based structures in cells, whether septins organize as filaments in cells and if septin organization impacts septin function is not known.

is upregulated by fungal infection in a GPA-12 and STA-2-independent manner in the epidermis.

Skin infection with the fungus leads to a transcriptional response in the worm epidermis. This involves an increased expression of a group of antimicrobial peptide (AMP) genes including those in the and clusters. The major pathways leading to the expression of these AMP genes have been well characterized and converge on the STAT transcription factor STA-2.

Comparison of lipidome profiles of Caenorhabditis elegans-results from an inter-laboratory ring trial.

Introduction: Lipidomic profiling allows 100s if not 1000s of lipids in a sample to be detected and quantified. Modern lipidomics techniques are ultra-sensitive assays that enable the discovery of novel biomarkers in a variety of fields and provide new insight in mechanistic investigations. Despite much progress in lipidomics, there remains, as for all high throughput "omics" strategies, the need to develop strategies to standardize and integrate quality control into studies in order to enhance robustness, reproducibility, and usability of studies within specific fields and beyond.

mutants have an increased fungal spore adhesion that is not rescued by .

If the cuticle acts as a protective barrier against environmental insults, several pathogens have developed strategies that use it as a way to infect . The fungus produces spores that attach to the cuticle, before hyphae invade the body. Mutants with an altered surface coat, the outermost layer of the cuticle, including , , and show increased adhesion of fungal spores (Rouger et al, 2014; Zugasti et al, 2016).

New Strains for Tissue-Specific RNAi Studies in .

RNA interference is a powerful tool for dissecting gene function. In , ingestion of double stranded RNA causes strong, systemic knockdown of target genes. Further insight into gene function can be revealed by tissue-specific RNAi techniques.

Non-Canonical Caspase Activity Antagonizes p38 MAPK Stress-Priming Function to Support Development.

Recent studies have revealed non-canonical activities of apoptotic caspases involving specific modulation of gene expression, such as limiting asymmetric divisions of stem-like cell types. Here we report that CED-3 caspase negatively regulates an epidermal p38 stress-responsive MAPK pathway to promote larval development in C. elegans.

Evolutionary plasticity in the innate immune function of Akirin.

Eukaryotic gene expression requires the coordinated action of transcription factors, chromatin remodelling complexes and RNA polymerase. The conserved nuclear protein Akirin plays a central role in immune gene expression in insects and mammals, linking the SWI/SNF chromatin-remodelling complex with the transcription factor NFκB. Although nematodes lack NFκB, Akirin is also indispensable for the expression of defence genes in the epidermis of Caenorhabditis elegans following natural fungal infection.

Modulatory upregulation of an insulin peptide gene by different pathogens in C. elegans.

When an animal is infected, its innate immune response needs to be tightly regulated across tissues and coordinated with other aspects of organismal physiology. Previous studies with Caenorhabditis elegans have demonstrated that insulin-like peptide genes are differentially expressed in response to different pathogens. They represent prime candidates for conveying signals between tissues upon infection.

Coordinated inhibition of C/EBP by Tribbles in multiple tissues is essential for Caenorhabditis elegans development.

Background: Tribbles proteins are conserved pseudokinases that function to control kinase signalling and transcription in diverse biological processes. Abnormal function in human Tribbles has been implicated in a number of diseases including leukaemia, metabolic syndromes and cardiovascular diseases. Caenorhabditis elegans Tribbles NIPI-3 was previously shown to activate host defense upon infection by promoting the conserved PMK-1/p38 mitogen-activated protein kinase (MAPK) signalling pathway.

A quantitative genome-wide RNAi screen in C. elegans for antifungal innate immunity genes.

Background: Caenorhabditis elegans has emerged over the last decade as a useful model for the study of innate immunity. Its infection with the pathogenic fungus Drechmeria coniospora leads to the rapid up-regulation in the epidermis of genes encoding antimicrobial peptides. The molecular basis of antimicrobial peptide gene regulation has been previously characterized through forward genetic screens.

The human PDZome: a gateway to PSD95-Disc large-zonula occludens (PDZ)-mediated functions.

Protein-protein interactions organize the localization, clustering, signal transduction, and degradation of cellular proteins and are therefore implicated in numerous biological functions. These interactions are mediated by specialized domains able to bind to modified or unmodified peptides present in binding partners. Among the most broadly distributed protein interaction domains, PSD95-disc large-zonula occludens (PDZ) domains are usually able to bind carboxy-terminal sequences of their partners.

The pseudokinase NIPI-4 is a novel regulator of antimicrobial peptide gene expression.

Hosts have developed diverse mechanisms to counter the pathogens they face in their natural environment. Throughout the plant and animal kingdoms, the up-regulation of antimicrobial peptides is a common response to infection. In C.

Unusual regulation of a STAT protein by an SLC6 family transporter in C. elegans epidermal innate immunity.

The cuticle and epidermis of Caenorhabditis elegans provide the first line of defense against invading pathogens. Upon invasion by the fungal pathogen Drechmeria coniospora, C. elegans responds by upregulating the expression of antimicrobial peptides (AMPs) in the epidermis via activation of at least two pathways, a neuroendocrine TGF-β pathway and a p38 MAPK pathway.

A genome-wide study of PDZ-domain interactions in C. elegans reveals a high frequency of non-canonical binding.

Background: Proteins may evolve through the recruitment and modification of discrete domains, and in many cases, protein action can be dissected at the domain level. PDZ domains are found in many important structural and signaling complexes, and are generally thought to interact with their protein partners through a C-terminal consensus sequence. We undertook a comprehensive search for protein partners of all individual PDZ domains in C.