The Chin-Sang Lab Reads

Papers Selected in 2011


VAB-1 can function in P9/10 epidermal cells as well as in neurons in the  pocket cell ventral enclosure and functions redundantly with PLX-2/plexin to prevent gaps in the bridge used for P9/10 cell migration in body wall closure.

 

Ephrins (B1 and B2) bind to IL-7 receptor alpha to modulate its internalization and signaling.

 

EphA and B receptors cocluster, such that specific ligation of one receptor promotes recruitment and cross-activation of the other.

 

An explanation for incomplete penetrance.  See this News and Views.

 

Viral silencing agents, viRNAs, are transgenerationally transmitted in a template-independent manner and work in trans to silence viral genomes present in animals that are deficient in producing their own viRNAs.

 

This review focuses on recent progress in elucidating molecular interaction networks using different kinds of functional assays in the classical genetic model for animal development.

 

An automated system simultaneously images worm behavior and neuronal Ca2+ transients .

 

A Caenorhabditis elegans heterologous expression system able to produce milligram amounts of functional native and engineered GPCRs. Both bovine opsin [(b)opsin] and human adenosine A(2A) subtype receptor [(h)A(2A)R] expressed in neurons or muscles of C. elegans were localized to cell membranes. Worms expressing these GPCRs manifested changes in motor behavior in response to light and ligands, respectively. Also see this paper.

 

MiniSOG may do for EM what Green Fluorescent Protein did for fluorescence microscopy. See also this paper on using Mito-MiniSOG for targeted cell ablations.

 

 

hif-1 is required for most, if not all, early transcriptional changes in H2S. Moreover, SKN-1, the C. elegans homologue of NRF2, also contributes to H2S-dependent changes in transcription asskn-1 is essential to survive exposure to H2S.

 

Skin wounding in C. elegans triggers a Ca2+-dependent signaling cascade that promotes wound closure, in parallel to the innate immune response to damage. Wound closure requires actin polymerization and is negatively regulated by nonmuscle myosin.

 

 

 

 

A novel role for DAF-18 in promoting neurite outgrowth during development in Caenorhabditis elegans.  DAF-18/PTEN acts cell-autonomously to control neurite length in the AIY interneurons. DAF-16B isoform is required downstream of DAF-18 for outgrowth

 

MADD-4 is secreted by the dorsal and ventral nerve cords of the nematode C. elegans to attract sensory axons and muscle membrane extensions called muscle arms. MADD-4's activity is dependent on UNC-40/DCC, a netrin receptor, which functions cell-autonomously to direct membrane extension.

 

 

Another successful chemical genomics project from the Peter Roy's lab. Dafadine an inhibitor of DAF-9.

 

These results indicate that the maternal environment affects both progeny reproduction and development in C. elegans and therefore that all progeny are not equal.

Both the initial double-stranded RNA (dsRNA), which triggers RNAi, and at least one dsRNA intermediate produced during RNAi can act as or generate mobile silencing RNA in C. elegans.

 

 

The transgenerational inheritance of lifespan extension by members of the ASH-2 complex is dependent on the H3K4me3 demethylase RBR-2, and requires the presence of a functioning germline in the descendants.

 

New technologies for C. elegans.

 

New method to follow RNA in vivo.

 

Selected >650 C. elegans genes based on their orthology to human genes and potential neuronal function or known biochemical role were crossed to the mec-4::gfp or mec-7::gfp markers and looked at PLM regeneration. Arf Guanine nucleotide Exchange Factor (GEF), EFA-6, acts as an intrinsic inhibitor of regrowth. They also report PLM overshoot and undershoot for many mutants tested.

 

motoneuron commissural axon morphology defects in mig-15 mutants result from impaired growth cone motility and subsequent failure to migrate across longitudinal obstacles or retract extra processes. ezrin/radixin/moesin ortholog ERM-1, the kinesin-1 motor UNC-116 and the actin regulator WVE-1 complex. Genetic analysis indicates that mig-15 and erm-1 act in the same genetic pathway to regulate growth cone migration and that this pathway functions in parallel to the UNC-116/WVE-1 pathway.

 

 

 

 

 

 

The hemidesmosome is not only structural but a mechanosensor that responds to tension that can stimulate signalling pathways. See Dispatch by Jeff Hardin

http://dx.doi.org/10.1016/j.cub.2011.03.052

 

 

A 554 essential genes network based on gonad phenotypes.  Watch Cell Paperclip

movies\Green et al 2011 High resolution C. elegans essential gene network.mp4

 

Selected by Ahmed: Robo1 interacts with Nrp1 to modulate semaphorin signaling in the developing forebrain. another example of Robo receptors forming putative hetero-receptor complexes. 

 

 

 

The decision for worms to leave their food is multigenic trait that is regulated by non-coding plymorphisms in tyra-3 (tyramine receptor 3). 

 

An update of Cell's most cited article.

The complete genomes of seven prostate tumours. Many rearrangements found. Rearrangement breakpoints were enriched near open chromatin, androgen receptor and ERG DNA binding sites in the setting of the ETS gene fusion TMPRSS2–ERG, but inversely correlated with these regions in tumours lacking ETS fusions.  Prostate cancer genes include PTEN, MAGI2, CADM2, 

 

Latest review of Eph in stem cells and cancer.

 

Yang et al. show that ephrin-A1 ligand-dependent activation of EphA2 decreases the growth of PC3 prostate cancer cells and profoundly inhibits the Akt-mTORC1 pathway, which is hyperactivated due to loss of the PTEN tumor suppressor. Their data suggest a novel signaling mechanism whereby EphA2 inactivates the Akt-mTORC1 oncogenic pathway through Aktdephosphorylation mediated by a serine/threonine phosphatase (PP1-like?).