An extracellular matrix protein promotes anillin-dependent processes in theCaenorhabditis elegansgermline

Abstract

Cell division requires constriction of an actomyosin ring to segregate the genetic material equally into two daughter cells. The spatial and temporal regulation of the contractile ring at the division plane primarily depends on intracellular signals mediated by the centralspindlin complex and astral microtubules. Although much investigative work has elucidated intracellular factors and mechanisms controlling this process, the extracellular regulation of cytokinesis remains unclear. Thus far, the extracellular matrix protein Hemicentin (HIM-4) has been proposed to be required for cleavage furrow stabilization. The underlying molecular mechanism, however, has remained largely unknown. Here, we show that HIM-4 and anillin (ANI-1) genetically act in the same pathway to maintain the rachis bridge stability in the germline. Our FRAP experiments further reveal that HIM-4 restricts the motility of ANI-1. In addition, we demonstrate that HIM-4 is recruited to the cleavage site in dividing germ cells and promotes the proper ingression of the cleavage membrane. Collectively, we propose that HIM-4 is an extracellular factor that regulates ANI-1 for germ cell membrane stabilization and contractile ring formation in Caenorhabditis elegans germline cells.

A Transcription Factor Functional Atlas of Germline Development

“…Of these TFs, only NHR-114 had previously been associated with germ cell multinucleation in C. elegans (Gracida and Eckmann, 2013). We used confocal microscopy to analyze the PZ of one-day adults following GTF silencing and detected no MNCs, suggesting that MNC formation is not due to aberrant mitotic division, as shown previously (data not shown) (Lan et al, 2019).…”

“…Persistent MNCs would generate multinuclear oocytes and infertile embryos and are therefore cleared by apoptosis prior to generating gametes. Earlier studies showed that failed germ cell division in the PZ and an unstable rachis can cause multinucleation, while in other cases, including in wild-type animals, MNCs form at specific germline structures called folds (Lan et al, 2019;Raiders et al, 2018). In our primary screen, we identified 26 GTFs that have >25% increase in germ lines with MNCs compared to control animals (Table S5-6).…”

SRPX and HMCN1 regulate cancer‑associated fibroblasts to promote the invasiveness of ovarian carcinoma

“…HMCN1 (also known as fibulin-6) (39) was first found in Caenorhabditis elegans, was named high incidence of males 4 and is one of the genes responsible for increased X chromosome loss in nematodes (40). Functionally, HMCN1 is associated with a hemidesmosome-type structure and is involved in extracellular adhesion, forming cell-cell and cell-basement membrane adhesions that hold cells together and maintain tissue and organ integrity (41).…”

Cortical recruitment of centralspindlin and RhoA effectors during meiosis I of Caenorhabditis elegans primary spermatocytes

“…Unlike germ cells in the mitotic zone of the gonad in C. elegans (Lan et al, 2019), primary spermatocytes are oriented regularly at the proximal end of the gonad in late-L4 worms, and their division entry is stereotyped (Fig. 6).…”