nematodes colonize ephemeral resource patches in neotropical forests.

Factors shaping the distribution and abundance of species include life-history traits, population structure, and stochastic colonization-extinction dynamics. Field studies of model species groups help reveal the roles of these factors. Species of nematodes are highly divergent at the sequence level but exhibit highly conserved morphology, and many of these species live in sympatry on microbe-rich patches of rotten material.

The Ancestral Cuticle Suppresses .

Genetic background commonly modifies the effects of mutations. We discovered that worms mutant for the canonical gene, identified by Brenner in 1974, do not roll in the genetic background of the wild strain CB4856. Using linkage mapping, association analysis and gene editing, we determined that N2 carries an insertion in the collagen gene that acts as a recessive enhancer of rolling.

Vertical transmission in nematodes of RNA molecules encoding a viral RNA-dependent RNA polymerase.

Here, we report on the discovery in nematodes of multiple vertically transmitted RNAs coding for putative RNA-dependent RNA polymerases. Their sequences share similarity to distinct RNA viruses, including bunyaviruses, narnaviruses, and sobemoviruses. The sequences are present exclusively as RNA and are not found in DNA form.

Comparative genomics of 10 new species.

The nematode has been central to the understanding of metazoan biology. However, is but one species among millions and the significance of this important model organism will only be fully revealed if it is placed in a rich evolutionary context. Global sampling efforts have led to the discovery of over 50 putative species from the genus , many of which await formal species description.

Interaction of the Chromatin Remodeling Protein hINO80 with DNA.

The presence of a highly conserved DNA binding domain in INO80 subfamily predicted that INO80 directly interacts with DNA and we demonstrated its DNA binding activity in vitro. Here we report the consensus motif recognized by the DBINO domain identified by SELEX method and demonstrate the specific interaction of INO80 with the consensus motif. We show that INO80 significantly down regulates the reporter gene expression through its binding motif, and the repression is dependent on the presence of INO80 but not YY1 in the cell.

Crossover heterogeneity in the absence of hotspots in Caenorhabditis elegans.

Crossovers play mechanical roles in meiotic chromosome segregation, generate genetic diversity by producing new allelic combinations, and facilitate evolution by decoupling linked alleles. In almost every species studied to date, crossover distributions are dramatically nonuniform, differing among sexes and across genomes, with spatial variation in crossover rates on scales from whole chromosomes to subkilobase hotspots. To understand the regulatory forces dictating these heterogeneous distributions a crucial first step is the fine-scale characterization of crossover distributions.