Matus, David Q. et al. (2013) International Worm Meeting "NHR-67 mediates cell cycle arrest and promotes the differentiation of the invasive phenotype."

Kelley, Laura C., Barkoulas, Michalis, Felix, Marie-Anne, Chi, Qiuyi, Matus, David Q., Sherwood, David R., Schindler, Adam J.

[International Worm Meeting, 2013]

There is a well-established link between cell cycle arrest and the transcriptional regulation of cell differentiation. Emerging data suggests that the complex cell biological movements orchestrated during morphogenesis (e.g. epithelial to mesenchymal transition (EMT) and convergent extension) also require cell cycle arrest to be properly executed. Cell invasion through basement membrane (BM) is a poorly understood morphogenetic behavior that occurs during development, immune surveillance and is mis-regulated during cancer metastasis. To functionally dissect cell invasive behavior at single-cell resolution, we are using the simple in vivo model of anchor cell (AC) invasion during C. elegans larval development. The AC, a specialized somatic gonadal cell, undergoes a BM transmigration event to connect the developing uterine and vulval tissues. In order to identify transcriptional regulators of AC invasion, we performed a uterine-specific transcription factor based RNAi screen, which identified the conserved nuclear hormone receptor, NHR-67/TLX. Strikingly, loss of NHR-67 results in multiple ACs that fail to invade. Through laser ablation, GFP reporter analyses and single molecule fluorescence in situ hybridization we show that NHR-67-depleted ACs arise from a single mitotic AC that expresses markers of an active cell cycle. Halting cell cycle progression by inducing a G1/G0 arrest in NHR-67-depleted animals rescues the invasion defect, demonstrating that cell cycle arrest is required for invasion. Blocking the cell cycle in the S or G2 phase failed to rescue AC invasion, indicating a specific requirement for a G1/G0 arrest. Time-lapse microscopy shows that mitotic ACs lack invadopodia, subcellular structures within the AC that function to breach the BM. Mitotic ACs also show reduced expression of downstream markers of invasive differentiation, including matrix metalloproteinases (MMPs). Our data indicates the requirement for the precise transcriptional control of a genetic program that links a G1/G0-specific cell cycle arrest to the differentiation of the invasive phenotype.

Matus, David Q et al. (2011) International Worm Meeting "NHR-67, a key transcription factor that maintains C. elegans anchor cell identity and the invasive phenotype."

Sherwood, David R, Chi, Qiuyi, Schindler, Adam J, Matus, David Q

[International Worm Meeting, 2011]

The transcriptional networks that specify and regulate the ability of a cell to traverse the boundaries imposed by basement membranes (BMs) are poorly characterized. This is largely due to the difficulties of studying this complex and dynamic event in vivo. Cell invasion is a critical cell biological process that occurs during normal development, immune surveillance, and is mis-regulated during metastatic cancer. Utilizing the simple model of C. elegans anchor cell (AC) invasion, we have previously identified four transcription factors (MEP-1, FOS-1A, EGL-43L, and HLH-2) and several downstream targets (cdh-3, zmp-1, hemicentin, T03F1.8) that function to regulate distinct aspects of AC invasion. We screened by RNAi 698 C. elegans transcription factors in a uterine-specific RNAi sensitive background, and identified the vertebrate tailless ortholog, NHR-67, as a potent regulator of AC invasion. Reduction in NHR-67 function by RNAi, loss-of-function alleles, and an AC-specific dominant negative NHR-67 construct suggest that NHR-67 functions at multiple levels to regulate the ability of the AC to initiate a BM transmigration program. NHR-67 is expressed in the gonadal lineage leading to the AC, where it appears to regulate the LIN-12/LAG-2 (Notch/Delta) signaling event that specifies the AC. Following Notch-mediated AC specification, loss of NHR-67 results in the presence of multiple ACs that express markers of an active cell cycle (rnr::GFP and cye-1>GFP), suggesting that NHR-67 functions downstream of Notch signaling to maintain the AC in a post-mitotic state. Loss of NHR-67 also inhibits AC invasion, where it appears to regulate multiple aspects of the invasion program, including the establishment of a specialized invasive cell membrane domain and the expression of the transcription factor FOS-1A and the guanylate kinase, T03F1.8. Taken together, these data suggest that NHR-67 functions at a key node in the gene regulatory network that both maintains and promotes the ability of the AC to invade.

Zarkower D et al. (1994) Worm Breeder's Gazette "mab-3 YAC Rescue"

De Bono M, Hodgkin JA, Zarkower D

[Worm Breeder's Gazette, 1994]

mab-3 YAC rescue David Zarkower, Mario de Bono, and Jonathan Hodgkin MRC Laboratory of Molecular Biology, Cambridge, England

Weinkove D (2018) BMC Biol "On microbes, aging and the worm: an interview with David Weinkove."

Weinkove D

[BMC Biol, 2018]

David Weinkove is an associate professor at Durham University, UK, studying host-microbe interactions in the model organism Caenorhabditis elegans. David has been focusing on the way microbes affect the physiology of their hosts, including the process of aging. In this interview, he discusses the questions shaping his research, how they evolved over the years, and his guiding principles for leading a lab.

Ewald AJ (2015) Dev Cell "An Arresting Story about Basement Membrane Invasion."

Ewald AJ

[Dev Cell, 2015]

In this issue of Developmental Cell, Matus et al. (2015) reveal that to invade past basement membrane, the C. elegans anchor cell must cease dividing before differentiating and expressing pro-invasion genes. This demonstration of invasion and proliferation as mutually incompatible cell states has implications for our understanding of cancer metastasis.

Miller DM et al. (1992) Worm Breeder's Gazette "unc-4 LacZ Expression in A-Type Motor Neurons"

Miller DM, Niemeyer CJ

[Worm Breeder's Gazette, 1992]

unc-4 LacZ expression in A-type motor neurons David M. Miller and Charles J. Niemeyer, Dept. of Cell Biology, Duke Univ. Medical Ctr, Durham, NC 27710

Grenache DG et al. (1993) Worm Breeder's Gazette "Differential Effects of Dauer-Defective Mutations in L1-Specific Surface Antigen Switching"

Politz SM, Grenache DG

[Worm Breeder's Gazette, 1993]

DIFFERENTIAL EFFECTS OF DAUER-DEFECTIVE MUTATIONS ON L1- SPECIFIC SURFACE ANTIGEN SWITCHING. David G. Grenache and Samuel M. Politz, Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA.

Smith, Jayson et al. (2019) International Worm Meeting "Investigating the role of the SWI/SNF chromatin remodeling complex in the differentiation of the invasive phenotype."

Smith, Jayson, Matus, David, Zhang, Wan

[International Worm Meeting, 2019]

The success of many metazoan developmental programs relies on the ability of specialized cells to transgress basement membranes (BMs). Cancer progression also relies on cellular invasion. Though the developmental and clinical importance of cell invasion is evident, studying its dynamics in vivo has proven to be challenging. Using high-resolution microscopy, as well as genetic and cell biological techniques, we study the process of anchor cell (AC) invasion into the vulval epithelium during C. elegans development as a model for cellular invasion. We have demonstrated that the conserved nuclear hormone receptor transcription factor, NHR-67, is required to maintain the AC in G1/G0 cell cycle arrest, a requirement for invasive behavior. Independent of cell cycle arrest, the AC utilizes the histone deacetylase, HDA-1, for the generation of invadopodia, and the expression of pro-invasive genes. These results suggest that invasion is a differentiated cellular behavior requiring cell cycle arrest and epigenetic modification of the genome. To identify additional chromatin modifiers that mediate invasion, we are conducting a tissue-specific RNAi screen. To date, we have identified several new pro-invasive genes which encode subunits of the SWI/SNF chromatin remodeling complex. The SWI/SNF complex is pleiotropic and contributes to cell fate specification in the somatic gonad and cell-cycle exit and differentiation of muscle and intestinal precursors in C. elegans. Here, we show a conserved role for the SWI/SNF complex in coordinating cell cycle arrest, as loss of swsn-1 results in a mitotic AC. We have endogenously GFP-tagged core SWI/SNF subunit SWSN-4 in order to confirm AC expression, and taking advantage of GFP-targeting nanobody technology, we are able to confirm a strong loss of invasion phenotype following SWSN-4::GFP depletion in the AC. Furthermore, we are examining the role of the SWI/SNF complex in maintenance of the post-mitotic state and the regulation of pro-invasive gene expression, through potential interactions with NHR-67, HDA-1, other chromatin modifiers and the cell cycle machinery. Using a DNA Helicase B-based CDK2 biosensor our lab has recently adapted to C. elegans, we are investigating the cell cycle state of the AC in chromatin modifier depleted states. Together, these results will provide insight into the role of the SWI/SNF complex in orchestrating invasive activity and coordinating exit from the cell cycle.

Emmons SW et al. (1994) Worm Breeder's Gazette "Strain Names for non-C. elegans Species."

Emmons SW, Fitch DHA, Leroi AM

[Worm Breeder's Gazette, 1994]

Strain names for non-C. elegans species Scott W. Emmonst, Armand Leroit, and David Fitch, Department of Molecular Genetics, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, Department of Biology, New York University, RmlOO9 Main Bldg., Washington Square, New York, NY 10003

Hall DH et al. (1994) Worm Breeder's Gazette "Cytology of Degenerin-Induced Cell Death in the PVM Neuron"

Driscoll MA, Chalfie M, Gu GQ, Hall DH, Gong L

[Worm Breeder's Gazette, 1994]

Cytology of degenerin-induced cell death in the PVM neuron David H. Hall, Guoqiang Gu+, Lei Gong#, Monica Driscoll#, and Martin Chalfie+, * Dept. Neuroscience, Albert Einstein College of Medicine, Bronx, N.Y. 10461 + Dept. Biological Sciences, Columbia University, New York, N.Y. 10027 # Dept. Molecular Biology and Biochemistry, Rutgers University, Piscataway, N.J. 08855