three species of paratylenchus were collected and identified from vineyards and apple orchards in kermanshah province, western iran. descriptions, morphometric data, line drawings and microscopic photographs are provided for these three species. paratylenchus audriellus and paratylenchus straeleni are the two very closely related species, with a stylet longer than 40 µm, four lateral lines and ...

The Mi-2 protein is the central component of the recently isolated NuRD nucleosome remodelling and histone deacetylase complex. Although the NuRD complex has been the subject of extensive biochemical analyses, little is known about its biological function. Here we show that the two C. elegans Mi-2 homologues, LET-418 and CHD-3, play essential roles during development. The two proteins possess b...

Massive vulval oedema is not common during pregnancy, but when it develops, it often is associated with patient discomfort and management challenges. Two pregnant women presented to Bugando Medical Centre in Mwanza, Tanzania, with massive swelling of the vulva at 39 weeks and 32 weeks of gestation. Both women were found to have multiple gestations. Despite medical management, there was no resol...

The development of the Caenorhabditis elegans vulva requires the involution of epithelial cells and provides a model for organ morphogenesis. Mutations in C. elegans sqv (squashed vulva) genes affect both vulval morphogenesis and embryonic development. We found that sqv-4 encodes a protein similar to UDP-glucose dehydrogenases and showed that the SQV-4 protein specifically catalyzes the convers...

The analysis of cell fate patterning during the vulval development of Caenorhabditis elegans has relied mostly on the direct observation of cell divisions and cell movements (cell lineage analysis). However, reconstruction of the developing vulva from EM serial sections has suggested seven different cell types (vulA, vulB1, vulB2, vulC, vulD, vulE, and vulF), many of which cannot be distinguish...

The let-23 gene encodes a Caenorhabditis elegans homolog of the epidermal growth factor receptor (EGFR) necessary for vulval development. We have characterized a mutation of let-23 that activates the receptor and downstream signal transduction, leading to excess vulval differentiation. This mutation alters a conserved cysteine residue in the extracellular domain and is the first such point muta...

An understanding of cell-invasive behavior has been limited by the lack of in vivo models where this activity can be clearly visualized and manipulated. We show that a single cell in the Caenorhabditis elegans gonad, the anchor cell (AC), initiates uterine-vulval contact through a cell invasion event. Using genetic analysis, laser ablations, and cell-specific markers, we demonstrate that AC inv...

Vulval differentiation in Caenorhabditis elegans involves several fundamental cellular events, including cell fusion, division and migration. We have characterized the role of the lin-40 (also known as egr-1) gene in these cellular processes. LIN-40 is homologous to the metastasis-associated factor 1 (MTA1) in mammals, which has been identified as a component of the nucleosome remodeling and hi...

The C. elegans PUF and FBF proteins regulate various aspects of germline development by selectively binding to the 3' untranslated region of their target mRNAs and repressing translation. Here, we show that puf-8, fbf-1 and fbf-2 also act in the soma where they negatively regulate vulvaI development. Loss-of-function mutations in puf-8 cause ectopic vulval differentiation when combined with mut...