The Abelson tyrosine kinase regulates Notch endocytosis and signaling to maintain neuronal cell fate in Drosophila photoreceptors.

The development of a functional organ requires coordinated programs of cell fate specification, terminal differentiation and morphogenesis. Whereas signaling mechanisms that specify individual cell fates are well documented, little is known about the pathways and molecules that maintain these fates stably as normal development proceeds or how their dysregulation may contribute to altered cell states in diseases such as cancer. In Drosophila, the tyrosine kinase Abelson (Abl) interfaces with multiple signaling pathways to direct epithelial and neuronal morphogenesis during embryonic and retinal development.

The tyrosine-sulfated peptide receptors PSKR1 and PSY1R modify the immunity of Arabidopsis to biotrophic and necrotrophic pathogens in an antagonistic manner.

The tyrosine-sulfated peptides PSKα and PSY1 bind to specific leucine-rich repeat surface receptor kinases and control cell proliferation in plants. In a reverse genetic screen, we identified the phytosulfokine (PSK) receptor PSKR1 as an important component of plant defense. Multiple independent loss-of-function mutants in PSKR1 are more resistant to biotrophic bacteria, show enhanced pathogen-associated molecular pattern responses and less lesion formation after infection with the bacterial pathogen Pseudomonas syringae pv.

Nemo phosphorylates Eyes absent and enhances output from the Eya-Sine oculis transcriptional complex during Drosophila retinal determination.

The retinal determination gene network comprises a collection of transcription factors that respond to multiple signaling inputs to direct Drosophila eye development. Previous genetic studies have shown that nemo (nmo), a gene encoding a proline-directed serine/threonine kinase, can promote retinal specification through interactions with the retinal determination gene network, although the molecular point of cross-talk was not defined. Here, we report that the Nemo kinase positively and directly regulates Eyes absent (Eya).

Functional analysis of receptor-like kinases in monocots and dicots.

Receptor-like kinases (RLKs) are signaling proteins that feature an extracellular domain connected via a transmembrane domain to a cytoplasmic kinase. This architecture indicates that RLKs perceive external signals, transducing them into the cell. In plants, RLKs were first implicated in the regulation of development, in pathogen responses, and in recognition events.

CCR5delta32, CCR2-64I, and SDF1-3'A polymorphisms related to resistance to HIV-1 infection and disease in the Ecuadorian population.

The aim of this study was to determine the allele frequencies of genetic variants CCR5delta32, CCR2-64I, and SDF1-3'A (SDF1 801 A), which influence susceptibility to HIV-1 infection. We also investigated the effect of these variants on the general Ecuadoran population and on a group of HIV-infected individuals to determine the frequency of these genetics variants.

Analysis of the polymorphism [gIVS12-6T > C] in the hMSH2 gene in lymphoma and leukemia.

Given the importance of mismatch repairing genes in keeping the genetic stability in cells, any alterations in their structure or function could generate instability in the genome and predispose the development of oncogenic processes. hMSH2 is the principal gene involved in the post-replicating DNA mismatch repair system. In this study, exon 13 of the hMSH2 gene was analyzed in different neoplasias, leukemias and lymphomas.

Low incidence of follicular lymphoma and t(14;18)(q32;q21) by polymerase chain reaction analysis. observations on Ecuadorian patients.

Translocation (14;18)(q32;q21) has been shown to be present in diagnostic tissue specimens from approximately 85% of patients with follicular lymphoma (FL) and 30% with diffuse non-Hodgkin lymphomas (NHL) in the USA. Also, there is evidence that the distribution of NHL subtypes differs by geographic region; however, there are no data for Ecuador. Using polymerase chain reaction, we examined the frequency of t(14;18) (MBR and mcr rearrangements) in 65 NHL samples collected through 5 years from the principal hospitals of Quito, Ecuador.

BCR-ABL rearrangement frequencies in chronic myeloid leukemia and acute lymphoblastic leukemia in Ecuador, South America.

Different BCR-ABL transcript variants occur more or less frequently, according to the leukemia type. We report the frequencies of BCR-ABL transcript variants studied in chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL) patients in the Ecuadorian population. The frequencies found for CML patients in this study were 94.