Live Imaging and Analysis of Muscle Contractions in Drosophila Embryo.

Coordinated muscle contractions are a form of rhythmic behavior seen early during development in Drosophila embryos. Neuronal sensory feedback circuits are required to control this behavior. Failure to produce the rhythmic pattern of contractions can be indicative of neurological abnormalities.

Mucin-type glycosylation as a regulatory factor of amyloid precursor protein processing.

Mucin-type O-glycosylation is found not only in mucus proteins, but also in a number of cell membrane and secretory proteins. Several recent studies demonstrate that site-specific O-GalNAc glycosylation plays an important role in regulating protein functions by modulating proteolytic processing. Proteolysis of the amyloid precursor protein (APP) is physiologically important, since cleavages at β and γ positions generate amyloid β (Aβ), a major component in the brain of patients with Alzheimer's disease.

Protein O-Mannosyltransferases Affect Sensory Axon Wiring and Dynamic Chirality of Body Posture in the Embryo.

Genetic defects in protein O-mannosyltransferase 1 (POMT1) and POMT2 underlie severe muscular dystrophies. genes are evolutionarily conserved in metazoan organisms. In , both male and female mutants show a clockwise rotation of adult abdominal segments, suggesting a chirality of underlying pathogenic mechanisms.

Shifting transcriptional machinery is required for long-term memory maintenance and modification in Drosophila mushroom bodies.

Accumulating evidence suggests that transcriptional regulation is required for maintenance of long-term memories (LTMs). Here we characterize global transcriptional and epigenetic changes that occur during LTM storage in the Drosophila mushroom bodies (MBs), structures important for memory. Although LTM formation requires the CREB transcription factor and its coactivator, CBP, subsequent early maintenance requires CREB and a different coactivator, CRTC.

Identification and expression analysis of zebrafish polypeptide α-N-acetylgalactosaminyltransferase Y-subfamily genes during embryonic development.

Mucin-type glycosylation is one of the most common posttranslational modifications of secretory and membrane proteins and has diverse physiological functions. The initial biosynthesis of mucin-type carbohydrates is catalyzed by UDP-GalNAc: polypeptide α-N-acetylgalactosaminyltransferases (GalNAc-Ts) encoded by GALNT genes. Among these, GalNAc-T8, -T9, -T17, and -T18 form a characteristic subfamily called "Y-subfamily" and have no or very low in vitro transferase activities when assayed with typical mucin peptides as acceptor substrates.

A rapid and efficient method for neuronal induction of the P19 embryonic carcinoma cell line.

Background: P19 mouse embryonic carcinoma cells are conventionally induced to differentiate into neural cells by suspension culture in the presence of retinoic acid to form cell aggregates, followed by adhesion culture in a poly-l-lysine-coated dish. Drawbacks of this procedure include it taking more than 10 days to obtain mature neurons, and non-neuronal proliferating cells occupying the majority of the cell population with time.

New Method: Here, we show a novel method for the rapid and efficient neurogenesis of P19 cells, without aggregate formation in a suspension culture.

GTDC2 modifies O-mannosylated α-dystroglycan in the endoplasmic reticulum to generate N-acetyl glucosamine epitopes reactive with CTD110.6 antibody.

Hypoglycosylation is a common characteristic of dystroglycanopathy, which is a group of congenital muscular dystrophies. More than ten genes have been implicated in α-dystroglycanopathies that are associated with the defect in the O-mannosylation pathway. One such gene is GTDC2, which was recently reported to encode O-mannose β-1,4-N-acetylglucosaminyltransferase.

A putative polypeptide N-acetylgalactosaminyltransferase/Williams-Beuren syndrome chromosome region 17 (WBSCR17) regulates lamellipodium formation and macropinocytosis.

We previously identified a novel polypeptide N-acetylgalactosaminyltransferase (GalNAc-T) gene, which is designated Williams-Beuren syndrome chromosome region 17 (WBSCR17) because it is located in the chromosomal flanking region of the Williams-Beuren syndrome deletion. Recent genome-scale analysis of HEK293T cells treated with a high concentration of N-acetylglucosamine (GlcNAc) demonstrated that WBSCR17 was one of the up-regulated genes possibly involved in endocytosis (Lau, K. S.

Protein O-mannosylation in animal development and physiology: from human disorders to Drosophila phenotypes.

Protein O-mannosylation has a profound effect on the development and physiology of mammalian organisms. Mutations in genes affecting O-mannosyl glycan biosynthesis result in congenital muscular dystrophies. The main pathological mechanism triggered by O-mannosylation defects is a compromised interaction of cells with the extracellular matrix due to abnormal glycosylation of alpha-dystroglycan.

Drosophila Dystroglycan is a target of O-mannosyltransferase activity of two protein O-mannosyltransferases, Rotated Abdomen and Twisted.

Recent studies highlighted an emerging possibility of using Drosophila as a model system for investigating the mechanisms of human congenital muscular dystrophies, called dystroglycanopathies, resulting from the abnormal glycosylation of alpha-dystroglycan. Several of these diseases are associated with defects in O-mannosylation, one of the most prominent types of alpha-dystroglycan glycosylation mediated by two protein O-mannosyltransferases. Drosophila appears to possess homologs of all essential components of the mammalian dystroglycan-mediated pathway; however, the glycosylation of Drosophila Dystroglycan (DG) has not yet been explored.

Cloning and expression of a brain-specific putative UDP-GalNAc: polypeptide N-acetylgalactosaminyltransferase gene.

We isolated a rat cDNA clone and its human orthologue, which are most homologous to UDP-GalNAc: polypeptide N-acetylgalactosaminyltransferase 9, by homology-based PCR from brain. Nucleotide sequence analysis of these putative GalNAc-transferases (designated pt-GalNAc-T) showed that they contained structural features characteristic of the GalNAc-transferase family. It was also found that human pt-GalNAc-T was identical to the gene WBSCR17, which is reported to be in the critical region of patients with Williams-Beuren Syndrome, a neurodevelopmental disorder, and to be predominantly expressed in brain and heart.

Characterization of a novel polypeptide N-acetylgalactosaminyltransferase (dGalNAc-T3) from Drosophila.

Polypeptide N-acetylgalactosaminyltransferases (GalNAc-transferases) catalyze the initial reaction of mucin-type O-glycosylation. Here, we report the first biochemical characterization of one of the Drosophila GalNAc-transferases, dGalNAc-T3. This enzyme retains conserved motifs essential for the catalytic activity, but is a novel isozyme in that it has several inserted sequences in its lectin-like domain.