RNAi Screen of RING/U-Box Domain Ubiquitin Ligases Identifies Critical Regulators of Tissue Regeneration in Planarians.

Regenerative processes depend on the interpretation of signals to coordinate cell behaviors. The role of ubiquitin-mediated signaling is known to be important in many cellular and biological contexts, but its role in regeneration is not well understood. To investigate how ubiquitylation impacts tissue regeneration , we are studying planarians that are capable of regenerating after nearly any injury using a population of stem cells.

Pathogenic Variability of Meloidogyne incognita Populations Occurring in Pepper-Production Greenhouses in Israel Toward Me1, Me3 and N Pepper Resistance Genes.

Natural variation in the root-knot nematode Meloidogyne incognita is problematic for breeding programs: populations possessing similar morphological characteristics can produce different reactions on the same host. We collected 30 widely dispersed M. incognita populations from protected pepper production systems in major pepper-growing regions of Israel and accurately identified their virulence characteristics by modified differential host test in a growth chamber on tomato, tobacco, cotton, melon, pepper, and peanut.

Meloidogyne javanica fatty acid- and retinol-binding protein (Mj-FAR-1) regulates expression of lipid-, cell wall-, stress- and phenylpropanoid-related genes during nematode infection of tomato.

Background: The secreted Meloidogyne javanica fatty acid- and retinol-binding (FAR) protein Mj-FAR-1 is involved in nematode development and reproduction in host tomato roots. To gain further insight into the role of Mj-FAR-1 in regulating disease development, local transcriptional changes were monitored in tomato hairy root lines with constitutive mj-far-1 expression compared with control roots without inoculation, and 2, 5 and 15 days after inoculation (DAI), using mRNA sequencing analysis.

Results: Gene-expression profiling revealed a total of 3970 differentially expressed genes (DEGs) between the two lines.

Responses of tomato genotypes to avirulent and Mi-virulent Meloidogyne javanica isolates occurring in Israel.

The behavior of naturally virulent Meloidogyne isolates toward the tomato resistance gene Mi in major tomato-growing areas in Israel was studied for the first time. Virulence of seven selected isolates was confirmed over three successive generations on resistant (Mi-carrying) and susceptible (non-Mi-carrying) tomato cultivars. Diagnostic markers verified the predominance of Meloidogyne javanica among virulent isolates selected on resistant tomato cultivars or rootstocks.

Two closely related members of Arabidopsis 13-lipoxygenases (13-LOXs), LOX3 and LOX4, reveal distinct functions in response to plant-parasitic nematode infection.

The responses of two closely related members of Arabidopsis 13-lipoxygenases (13-LOXs), LOX3 and LOX4, to infection by the sedentary nematodes root-knot nematode (Meloidogyne javanica) and cyst nematode (Heterodera schachtii) were analysed in transgenic Arabidopsis seedlings. The tissue localization of LOX3 and LOX4 gene expression using β-glucuronidase (GUS) reporter gene constructs showed local induction of LOX3 expression when second-stage juveniles reached the vascular bundle and during the early stages of plant-nematode interaction through gall and syncytia formation. Thin sections of nematode-infested knots indicated LOX3 expression in mature giant cells, and high expression in neighbouring cells and those surrounding the female body.

Fatty acid-and retinol-binding protein, Mj-FAR-1 induces tomato host susceptibility to root-knot nematodes.

Plant-parasitic nematodes produce at least one structurally unique class of small helix-rich retinol- and fatty-acid-binding proteins that have no counterparts in their plant hosts. Herein we describe a protein of the plant-parasitic root-knot nematode Meloidogyne javanica, which is a member of the nematode-specific fatty-acid- and retinol-binding (Mj-FAR-1) family of proteins. The mj-far-1 mRNA was detected through M.