A switch in collagen expression regulates cessation of distal tip cell migration in C. elegans

Matrix Biology · 2026-02-19 · 1 citations

Development of the C. elegans gonad requires precise regulation of cell migration. The distal tip cell (DTC) guides the elongation of the gonad into its final U-shaped structure before halting in adulthood. How cessation of elongation is regulated remains unknown. Here, we analyze an RNA-seq data set isolated from stage-specific DTCs to uncover the temporal gene expression dynamics underlying this process. Collagens emerged as the most enriched gene family during the transition from migratory larval stages to adulthood. We identify distinct temporal waves of collagen expression, culminating in a core adult-specific module that coincides with migration cessation. Functional analysis by RNAi depletion and analysis of mutant alleles revealed that many collagens are required for timely migration arrest, while others affect gonad shape. Perturbation of collagen remodeling enzymes phenocopied these defects. Our findings uncover a stage-specific collagen expression program in the DTC and suggest that basement membrane and cuticle collagens contribute to the termination of gonad elongation.

Stage-specific transcriptomics of a leader cell reveals cell machineries driving collective invasion

The Journal of Cell Biology · 2026-03-19 · 1 citations

Collective cell invasion underlies organ development, epithelial repair, and cancer metastasis. "Leader cells" remodel ECM, sense guidance cues, reorganize their cytoskeleton, and coordinate follower cells, but the molecular programs enabling these functions remain unclear. Here, we present a stage-specific transcriptomic dataset of the Caenorhabditis elegans gonadal leader cell, the distal tip cell (DTC), which invades basement membrane and guides germ cells to form U-shaped gonadal arms. Comparing invasive larval-stage DTCs with noninvasive adult-stage DTCs defines the molecular signature of an actively invading leader cell in vivo. Our dataset recapitulates known regulators of gonad morphogenesis and reveals numerous uncharacterized genes with potential roles in leader cell activity. Demonstrating dataset utility, we identify vesicular trafficking proteins enriched in invading DTCs and demonstrate their importance for gonad development using endogenous tagging and DTC-specific RNAi. We also catalog diverse DTC-specific knockdown phenotypes. This resource establishes a molecular framework for leader cell activity and a platform to investigate conserved mechanisms of invasive migration.

Stage-specific transcriptomics of a leader cell reveals functional machineries driving collective invasion

bioRxiv (Cold Spring Harbor Laboratory) · 2025-10-01 · 1 citations

Abstract Collective cell invasion underlies organ development, epithelial repair, and cancer metastasis. “Leader cells” remodel extracellular matrix, sense guidance cues, reorganize their cytoskeleton, and coordinate follower cells, but the molecular programs enabling these functions remain unclear. Here, we present a stage-specific transcriptomic dataset of the C. elegans gonadal leader cell, the distal tip cell (DTC), which invades basement membrane and guides germ cells to form U-shaped gonadal arms. Comparing invasive larval-stage DTCs with non-invasive adult-stage DTCs defines the molecular signature of an actively invading leader cell in vivo . Our dataset recapitulates known regulators of gonad morphogenesis and reveals numerous uncharacterized genes with potential roles in leader cell activity. As proof of concept, we identify vesicular trafficking proteins as enriched in invading DTCs, and demonstrate their importance for gonad development using endogenous tagging and DTC-specific RNAi. We also catalog diverse DTC-specific knockdown phenotypes. This resource establishes a molecular framework for leader cell activity and a platform to investigate conserved mechanisms of invasive migration.

On-Demand Delivery of Fibulin-1 Protects the Basement Membrane During Cyclic Stretching

SSRN Electronic Journal · 2025-01-01

On-demand delivery of fibulin-1 protects the basement membrane during cyclic stretching in C. elegans

Developmental Cell · 2025-08-13 · 4 citations

GOA-1 regulates spermathecal transits

PubMed · 2025-09-30 · 2 citations

spermatheca. In this study, we show that the inhibitory Gαi/o subunit GOA-1 regulates spermathecal transit. We employed TurboID proximity labeling and mass spectrometry to identify 16 candidate interactors of GOA-1 . Depletion of these candidates by RNAi did not yield overt spermathecal transit defects.

A switch in collagen expression regulates cessation of distal tip cell migration in <i>C. elegans</i>

bioRxiv (Cold Spring Harbor Laboratory) · 2025-10-03 · 1 citations

gonad requires precise regulation of cell migration. The distal tip cell (DTC) guides the elongation of the gonad into its final U-shaped structure before halting in adulthood. How cessation of elongation is regulated remains unknown. Here, we analyze an RNA-seq data set isolated from stage-specific DTCs to uncover the temporal gene expression dynamics underlying this process. Collagens emerged as the most enriched gene family during the transition from migratory larval stages to adulthood. We identify distinct temporal waves of collagen expression, culminating in a core adult-specific module that coincides with migration cessation. Functional analysis by RNAi depletion revealed that many collagens upregulated in adulthood are required for timely migration arrest, while others affect gonad shape. Perturbation of collagen remodeling enzymes phenocopied these effects. Our findings uncover a stage-specific collagen program in the DTC and suggest that terminal migration arrest is actively reinforced by matrix remodeling.

Identification of DELLA and GID1 genes in Catharanthus roseus and their potential role in regulating vindoline biosynthesis

Plant Molecular Biology · 2025-06-01

DELLAs are key regulators of plant growth and development, negatively regulating gibberellic acid (GA) signaling and positively regulating light and jasmonate signaling and juvenile leaf development. In the presence of GA, GID1s bind to DELLAs and signal for their degradation. Here, we identified and characterized DELLA and GID1 genes in Catharanthus roseus, the natural source of chemotherapy drugs vinblastine and vincristine. We hypothesized that CrDELLAs positively regulate vindoline biosynthesis, a precursor of vinblastine and vincristine, accumulating in light- and jasmonate-exposed young leaves. To explore this hypothesis, we silenced CrDELLA or CrGID1 genes using virus-induced gene silencing. CrDELLA-silenced plants were elongated while CrGID1-silenced plants were dwarfed, consistent with their roles in GA-mediated growth. In the first experiment, CrDELLA-silencing significantly decreased vindoline pathway gene expression while CrGID1-silencing significantly increased vindoline, catharanthine, ajmalicine, and serpentine accumulation. However, subsequent experiments found little to no effect. C. roseus seedlings treated with paclobutrazol, an inhibitor of GA biosynthesis shown to increase DELLA protein stability, also provided some evidence for CrDELLA’s positive role in regulating vindoline pathway gene expression. Finally, overexpressed stabilized, N-terminal truncated CrDELLAs in C. roseus seedlings yielded significant increases in vindoline pathway promoter activity (NMT, D4H). Overall, these experiments provide weak to moderate evidence for CrDELLAs positively regulating vindoline biosynthesis. Future experiments with transgenic approaches could strengthen the evidence and clarify this relationship. Activation of the vindoline pathway with stabilized CrDELLAs could increase the production of critical chemotherapeutics, vinblastine and vincristine. Transient silencing of CrDELLAs and CrGID1s, overexpression of truncated CrDELLAs, and application of the gibberellic acid-inhibitor paclobutrazol provide weak to moderate evidence that CrDELLAs activate vindoline biosynthesis in Catharanthus roseus.

On-demand delivery of fibulin-1 enables repeated basement membrane stretching

bioRxiv (Cold Spring Harbor Laboratory) · 2025-02-03 · 1 citations

Basement membrane (BM) extracellular matrices enwrap and structurally support tissues. Whether BMs are uniquely constructed to support tissues that undergo repetitive stretching and recoil events is unknown. During C. elegans ovulation, the spermathecal BM stretches ~1.7-fold and then returns to its original shape every twenty minutes to passage hundreds of oocytes. Through live fluorescence microscopy, we discovered that ovulating oocytes secrete and deliver the fibulin-1 extracellular matrix protein to the spermathecal BM during stretching, where it forms a dynamic overlapping network with type IV collagen. Fibulin-1 depletion led to a breakdown in type IV collagen and BM organization, resulting in a more deformable BM and extended spermatheca. Moreover, perturbation to fibulin-1 network formation via mutagenesis was sufficient to disrupt organ shape. Together, our study reveals an on-demand fibulin-1 delivery system that protects the BM network when it is stretched, thereby allowing repeated rounds of organ expansion and recovery.