Drosophila nasuta nasuta (2n = 8) and D. n. albomicans (2n = 6) are morphologically identical, cross fertile and karyotypically dissimilar pair of chromosomal races belonging to nasuta subgroup of immigrans group of Drosophila. Interracial hybridization between these two races yielded karyotypically stabilized newly evolved Cytoraces with new combinations of chromosomes and DNA content, and are called nasuta-albomicans complex of Drosophila.
Botulinum neurotoxins (BoNTs) are proteins of great interest not only because of their extreme toxicity but also paradoxically for their therapeutic applications. All the known serotypes (A-G) have varying degrees of longevity and potency inside the neuronal cell. Differential chemical modifications such as phosphorylation and ubiquitination have been suggested as possible mechanisms for their longevity, but the molecular basis of the longevity remains unclear.
Telomerases contain an essential RNA subunit (TER), as well as an essential protein reverse transcriptase subunit (TERT). The RNA subunit includes a short template region that is copied into telomeric DNA, but otherwise it is large and divergent. However, phylogenetic studies have revealed a conserved core secondary structure for TER. Much of the divergence can be accounted for by the acquisition of different types of RNA domains that function in RNA stabilization.
Mechanistic 'physics' models of protein folding fail to account for the observed spectrum and rate of protein folding and aggregation disorders in human populations, showing that more appropriately in vivo paradigms reflecting biological and other embedding contexts are needed for understanding the etiology, prevention, and treatment of these diseases. Here, a topological rate distortion analysis is applied to the problem that is analogous to Tlusty (2007) elegant exploration of the genetic code.
Intracellular calcium controls several crucial cellular events in apicomplexan parasites, including protein secretion, motility, and invasion into and egress from host cells. The plant compound thapsigargin inhibits the sarcoplasmic-endoplasmic reticulum calcium ATPase (SERCA), resulting in elevated calcium and induction of protein secretion in Toxoplasma gondii. Artemisinins are natural products that show potent and selective activity against parasites, making them useful for the treatment of malaria.
In this study, we investigated the influence of single nucleotide polymorphisms on the conformation of mutated cytochrome P450 (CYP) 2B6 proteins using molecular dynamics (MD) simulation. Some of these mutations influence drug metabolism activities, leading to individual variations in drug efficacy and pharmacokinetics. Using computational docking, we predicted the structure of the complex between the antimalarial agent artemether and CYP2B6 whose conformations were obtained by MD simulation.
Over 130 mutations to copper, zinc superoxide dismutase (SOD) are implicated in the selective death of motor neurons found in 25% of patients with familial amyotrophic lateral sclerosis (ALS). Despite their widespread distribution, ALS mutations appear positioned to cause structural and misfolding defects. Such defects decrease SOD's affinity for zinc, and loss of zinc from SOD is sufficient to induce apoptosis in motor neurons in vitro.
PURPOSE: To determine comparative effects of ultraviolet (UV)-A irradiation on structural and functional properties of wild type (WT) alphaB-crystallin and its three deamidated mutant proteins (alphaB-Asn78Asp, alphaB-Asn146Asp, and alphaB-Asn78/146Asp). METHODS: Three deamidated mutants previously generated from recombinant WT alphaB-crystallin, using a site-specific mutagenesis procedure as previously described , were used. The WT alphaB-crystallin and its three deamidated species were exposed to UV-A light (320-400 nm) at intensities of 20 or 50 J/cm(2).
Epidemiological evidence suggests that moderate consumption of red wine reduces the incidence of Alzheimer disease (AD). To study the protective effects of red wine, experiments recently were executed in the Tg2576 mouse model of AD. These studies showed that a commercially available grape seed polyphenolic extract, MegaNatural-AZ (MN), significantly attenuated AD-type cognitive deterioration and reduced cerebral amyloid deposition (Wang, J., Ho, L., Zhao, W., Ono, K., Rosensweig, C., Chen, L., Humala, N., Teplow, D. B., and Pasinetti, G. M. (2008) J. Neurosci. 28, 6388-6392).
Cardiac slow delayed rectifier (I(Ks)) channel complex consists of KCNQ1 channel and KCNE1 auxiliary subunits. The extracellular juxtamembranous region of KCNE1 is an unstructured loop that contacts multiple KCNQ1 positions in a gating-state-dependent manner. Congenital arrhythmia-related mutations have been identified in the extracellular S1-S2 linker of KCNQ1. These mutations manifest abnormal phenotypes only when coexpressed with KCNE1, pointing to the importance of proper KCNQ1/KCNE1 interactions here in I(Ks) channel function.