The binding of drugs by plasma proteins is an important phenomenon, because it influences the size of the free fraction of the drugs in plasma. In this study the influence of dipyridamole (DP) on the protein binding of propranolol (PL) and PL on the protein binding of DP were studied alone and in the presence of nicotine (NC).        The equilibrium dialysis was employed for protein bin...

NirA, the specific transcription factor of the nitrate assimilation pathway of Aspergillus nidulans, accumulates in the nucleus upon induction by nitrate. NirA interacts with the nuclear export factor KapK, which bridges an interaction with a protein of the nucleoporin-like family (NplA). Nitrate induction disrupts the NirA-KapK interaction in vivo, whereas KapK associates with NirA when this p...

Phosphorylation of the retinoblastoma protein (Rb) by the cyclin D1/cyclin-dependent kinase (cdk) 4 complex (cdk4/D1) is a key regulatory step for maintaining the orderly progression of the cell cycle. The B domain of Rb contains a site that recognizes and binds the LXCXE motif found in D-type cyclins. This interaction is important for phosphorylation of Rb by cdk4/D1, although in vitro the Rb ...

The human immunodeficiency virus (HIV) integrase (IN) protein mediates an essential step in the retroviral lifecycle, the integration of viral DNA into human DNA. A DNA-binding domain of HIV IN has previously been identified in the C-terminal part of the protein. We tested truncated proteins of the C-terminal region of HIV-1 IN for DNA binding activity in two different assays: UV-crosslinking a...

Background: Septins are members of highly conserved polymerizing GTP binding proteins well described in the animal kingdom. 14 Septin proteins have been characterized in humans (SEPT1-SEPT14), some of which are tissue-specific. All of 14 genome-mapped human septins contain a highly conserved central GTP-binding domain which is very critical in GTPase signaling properties as well as oligomerizat...

objective(s): mutant forms fms-like tyrosine kinase-3 (flt3), are reported in 25% of childhood acute lymphoid leukemia (all) and 30% of acute myeloid leukemia (aml) patients. in this study, drug response, growth promoting, and protein trafficking of flt3 wild-type was compared with two active mutants (internal tandem duplication (itd)) and d835y. materials and methods:flt3 was expressed on fact...

Leptin is a hormone produced in adipose cells that regulates energy expenditure, food intake, and adiposity. To understand leptin's transcriptional regulation, we are studying its promoter. Four conserved and functional regions were identified. Mutations in the C/EBP and TATA motifs each caused an approximately 10-fold decrease in promoter activity. The C/EBP motif bound recombinant C/EBP alpha...

The CBL ubiquitin ligase targets a variety of activated tyrosine kinases (TKs) for degradation. Many TKs are mutationally or autocrine activated and/or often overexpressed at the mRNA and protein levels in acute leukemias. We hypothesized that CBL is mutated in patients with acute myeloid leukemia (AML). Four of 12 patients and the MOLM-13 cell line harbored c-CBL mutations, either RNA splicing...

Congenital recessive myotonia is a rare genetic disorder caused by mutations in CLCN1, which codes for the main skeletal muscle chloride channel ClC-1. More than 120 mutations have been found in this gene. The main feature of this disorder is muscle membrane hyperexcitability. Here, we report a 59-year male patient suffering from congenital myotonia. He had transient generalized myotonia, which...