PAT-12, a potential anti-nematode target, is a new spectraplakin partner essential for Caenorhabditis elegans hemidesmosome integrity and embryonic morphogenesis

Abstract

Caenorhabditis elegans embryonic elongation depends on both epidermal and muscle cells. The hemidesmosome-like junctions, commonly called fibrous organelles (FOs), that attach the epidermis to the extracellular matrix ensure muscle anchoring to the cuticular exoskeleton and play an essential role during elongation. To further define how hemidesmosomes might control elongation, we searched for factors interacting with the core hemidesmosome component, the spectraplakin homolog VAB-10. Using the VAB-10 plakin domain as bait in a yeast two-hybrid screen, we identified the novel protein T17H7.4. We also identified T17H7.4 in an independent bioinformatic search for essential nematode-specific proteins that could define novel anti-nematode drug or vaccine targets. Interestingly, T17H7.4 corresponds to the C. elegans equivalent of the parasitic OvB20 antigen, and has a characteristic hemidesmosome distribution. We identified two mutations in T17H7.4, one of which defines the uncharacterized gene pat-12, previously identified in screens for genes required for muscle assembly. Using isoform-specific GFP constructs, we showed that one pat-12 isoform with a hemidesmosome distribution can rescue a pat-12 null allele. We further found that lack of pat-12 affects hemidesmosome integrity, with marked defects at the apical membrane. PAT-12 defines a novel component of C. elegans hemidesmosomes, which is required for maintaining their integrity. We suggest that PAT-12 helps maintaining VAB-10 attachment with matrix receptors.

Silencing of essential genes by RNA interference inHaemonchus contortus

“…The gene Ce-pat-12 (paralysed arrest at two-fold; T17H7·4), also known as Ce-gei-16 (gex interacting), encodes a protein with 27 predicted isoforms (www.wormbase.org), many of which have been confirmed (Hetherington et al 2011). The gene Ce-pat-12 (paralysed arrest at two-fold; T17H7·4), also known as Ce-gei-16 (gex interacting), encodes a protein with 27 predicted isoforms (www.wormbase.org), many of which have been confirmed (Hetherington et al 2011).…”

“…The gene Ce-pat-12 (paralysed arrest at two-fold; T17H7·4), also known as Ce-gei-16 (gex interacting), encodes a protein with 27 predicted isoforms (www.wormbase.org), many of which have been confirmed (Hetherington et al 2011). In addition, post-embryonic RNAi of Ce-pat-12 leads to paralysis and death, often associated with moulting defects and muscle detachment (Hetherington et al 2011). PAT-12 was initially chosen as a target as it has a high degree of homology to the B20 antigen from the filarial parasite Onchocerca volvulus (Abdel-Wahab et al 1996).…”

“…In C. elegans many of the isoforms of PAT-12 are expressed in the epidermis and also in the apical and basal plasma membranes of the pharynx. PAT-12 was subsequently shown to be a novel component of the hemidesmosome, which is essential to maintain the attachment of the body wall muscles to the cuticle (Hetherington et al 2011). In addition, post-embryonic RNAi of Ce-pat-12 leads to paralysis and death, often associated with moulting defects and muscle detachment (Hetherington et al 2011).…”

TheC. elegansUNC-23 protein, a member of the BCL-2-associated athanogene (BAG) family of chaperone regulators, interacts with HSP-1 to regulate cell attachment and maintain hypodermal integrity

“…12, [14][15][16][17][18][19][20] Mutations affecting the unc-23 gene were first isolated in a forward genetic screen designed to identify animals with visible mutant phenotypes. 21 Among the original 619 mutants that were identified, only Unc-23 mutant animals exhibited a progressive dystrophy of the head musculature resulting in a bent-head phenotype.…”

The Caenorhabditis elegans epidermis as a model skin. II: differentiation and physiological roles

“…cIF assembly and function is tightly regulated by several mechanisms, including post‐translational modification by SUMO 32. Intracellular components of TEAs also include the conserved ankyrin domain protein VAB‐19,33 its interacting partner, the PTB domain protein EPS‐8,34 and the nematode‐specific protein PAT‐12 35. All these components are essential for later epidermal elongation and muscle attachment.…”