NAD Acts as a Protective Factor in Cellular Stress Response to DNA Alkylating Agents.

Sulfur mustard (SM) and its derivatives are potent genotoxic agents, which have been shown to trigger the activation of poly (ADP-ribose) polymerases (PARPs) and the depletion of their substrate, nicotinamide adenine dinucleotide (NAD). NAD is an essential molecule involved in numerous cellular pathways, including genome integrity and DNA repair, and thus, NAD supplementation might be beneficial for mitigating mustard-induced (geno)toxicity. In this study, the role of NAD depletion and elevation in the genotoxic stress response to SM derivatives, i.

In vivo functional analysis of Drosophila protein kinase casein kinase 2 (CK2) beta-subunit.

Protein casein kinase 2 (CK2) is a heterotetramer composed of two catalytic (alpha) and two regulatory (beta) subunits. In Drosophila melanogaster, four genes encoding for one CK2alpha (DmCK2alpha) and three CK2beta (DmCK2beta, DmCK2beta' and DmCK2betates) subunits have been identified. Here, we have focused on the role of DmCK2beta.

Effects of the serine/threonine kinase SGK1 on the epithelial Na(+) channel (ENaC) and CFTR: implications for cystic fibrosis.

Cystic fibrosis (CF) is characterized by impaired Cl(-) secretion and increased Na(+) reabsorption in several tissues including respiratory epithelium. Many CFTR mutations have been identified over the past years. However, only a poor correlation between the genotype and lung phenotype was found suggesting additional factors influencing the phenotype and course of the disease.

The shrinkage-activated Na(+) conductance of rat hepatocytes and its possible correlation to rENaC.

At moderate cell shrinkage, activation of Na(+) channels is the most prominent mechanism of regulatory cell volume increase in rat hepatocytes. The amiloride sensitivity of these channels suggests a relation to the family of epithelial Na(+) channels (ENaCs). The present study was performed to determine the pharmacological profile of shrinkage-activated Na(+) channels and to test for ENaC expression in primary cultures of rat hepatocytes; in addition, the influence of the cell volume regulated serine/threonine kinase hSGK on activity and pharmacological profile of rENaC was examined in Xenopus oocytes.

Deranged transcriptional regulation of cell-volume-sensitive kinase hSGK in diabetic nephropathy.

Transforming growth factor beta (TGF-beta) has been shown to participate in the pathophysiology of diabetic complications. As shown most recently, TGF-beta stimulates the expression of a distinct serine/threonine kinase (hSGK) which had previously been cloned as an early gene transcriptionally regulated by cell volume alterations. The present study was performed to elucidate transcription and function of hSGK in diabetic nephropathy.

Mushroom body defect, a gene involved in the control of neuroblast proliferation in Drosophila, encodes a coiled-coil protein.

Neurogenesis relies on the establishment of the proper number and precisely controlled proliferation of neuroblasts, the neuronal precursor cells. A role for the mushroom body defect (mud) gene in both of these aspects of neuroblast behavior, as well as possible roles in other aspects of fruit fly biology, is implied by phenotypes associated with mud mutations. We have localized mud by determining the sequence change in one point mutant, identifying a predicted ORF affected by the mutation, and showing that an appropriate segment of the genome rescues mud mutant phenotypes.

A protein related to p21-activated kinase (PAK) that is involved in neurogenesis in the Drosophila adult central nervous system.

Brains are organized by the developmental processes generating them. The embryonic neurogenic phase of Drosophila melanogaster has been studied in detail at the genetic, cellular and molecular level. In contrast, much of what is known of postembryonic brain development has been gathered by neuroanatomical and gene expression studies.

Selective histamine uptake rescues photo- and mechanoreceptor function of histidine decarboxylase-deficient Drosophila mutant.

In insects, histamine is found both in the peripheral nervous system (PNS) and in the CNS and is known to function as a fast neurotransmitter in photoreceptors that have been shown to express selectively the hdc gene. This gene codes for histidine decarboxylase (HDC), the enzyme for histamine synthesis. Fast neurotransmission requires the efficient removal of the transmitter from the synaptic cleft.

Genetic depletion of histamine from the nervous system of Drosophila eliminates specific visual and mechanosensory behavior.

The role of histamine as a fast neurotransmitter of imaginal insect photoreceptors is firmly established. In adult Drosophila, histamine is also found in mechanosensory receptors of cuticular hair sensilla and in a small number of nonreceptor neurons in head and body ganglia. Here we investigate the function of histamine by immunohistochemical and behavioral analysis of mutants deficient in the hdc gene that codes for histidine decarboxylase.