Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.3.1.28 (chloramphenicol acetyltransferase)
 5,100 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The androgen receptor (AR) from a patient with Reifenstein syndrome (incomplete androgen insensitivity syndrome) was characterized. The patient's pubic skin fibroblasts had normal androgen binding. However, when incubated at 41 C, fibroblasts from the patient had a marked decrease in androgen binding as compared with normal fibroblasts. Analysis of coding sequences of the androgen receptor gene revealed a single nucleotide substitution in exon E, resulting in an amino acid change from glycine (GGG) to valine (GTG) at amino acid 743 within the steroid binding domain of AR. Reconstruction of this mutation by site-directed mutagenesis into a human AR complementary DNA followed by expression in COS1 cells led to production of a mutant AR with no significant difference in androgen binding when cells were incubated with androgen at room temperature. However, in contrast to wild type AR expressed in COS1 cells, the mutant AR had markedly lower androgen-binding affinity at 41 C. The mutant receptor could still stimulate a reporter gene at 37 C but this transcriptional stimulation was also decreased when compared with wild type AR receptor in a chloramphenicol acetyltransferase assay. These results suggest that partial androgen resistance in this patient with Reifenstein syndrome is due to a single point mutation in the steroid binding domain of the androgen receptor.
 ...
PMID:A single amino acid substitution (gly743 --> val) in the steroid-binding domain of the human androgen receptor leads to Reifenstein syndrome. 832 32

Molecular interactions between the herpes simplex virus type 1 (HSV-1) and human immunodeficiency virus (HIV) were investigated in U937 cells. Nonpermissive HSV-1 infection of U937 cells activated HIV as determined in transient expression assays with hybrid constructions containing the HIV-LTR-directed chloramphenicol acetyltransferase gene. Activation was independent of kappa B-enhancer elements whereas these elements were required for HSV-1-mediated activation in another cell line (C6). kappa B-binding proteins were induced in U937 cells by HSV-1 infection. Four species (45, 55, 75, and 75/80 kDa) were identified by DNA-protein cross-linking. Methylation interference analysis defined close contact only with the third residue of the previously established critical contact triplet GGG. Transient expression assays using mutants in HIV-LTR revealed the presence a cis-response element (GGTCA palindrome) in the negative regulatory region.
 ...
PMID:NF-kappa B-binding proteins induced by HSV-1 infection of U937 cells are not involved in activation of human immunodeficiency virus. 838 Jun 62

Genome analogs ("minigenomes") of Sendai and measles viruses replicate efficiently only if their nucleotide length is an even multiple of six, a requirement called the rule of six (P. Calain and L. Roux, J. Virol. 67:4822-4830, 1993; M. S. Sidhu, J. Chan, K. Kaelin, P. Spielhofer, F. Radecke, H. Schneider, M. Masurekar, P. C. Dowling, M. A. Billeter, and S. A. Udem, Virology 208:800-807, 1995). The existence of a comparable requirement was tested for respiratory syncytial virus (RSV), which also is a member of family Paramyxoviridae and whose natural genome length also is a multiple of six. An internally truncated analog of RSV positive-sense replicative intermediate RNA (antigenome) bearing the chloramphenicol acetyltransferase gene as a reporter was synthesized from cDNA in vitro. This RNA was transfected into cells which were infected with RSV as a helper. Miniantigenomic RNA was indistinguishable from previously studied negative-sense minigenome RNA in its ability to participate in transcription, RNA replication, and incorporation into transmissible particles. Sixteen miniantigenomes which were of slightly different lengths and which in aggregate represented multiples of a wide range of integers including 1 to 15 were constructed. During transfection and two serial passages, the various miniantigenomes were essentially indistinguishable with regard to the efficiency of transcription, RNA replication, and packaging into transmissible particles. Progeny minigenomes of six different mutants were recovered postpassage, copied into cDNA, cloned, and sequenced completely. The length of each of these RNAs was found to have remained unchanged during replication and passage. Thus, RSV transcription and replication appear to lack the requirement that the template length be an even multiple of an integer such as six, which for Sendai and measles viruses is obligatory for nucleocapsid function. Each of the in vitro-synthesized miniantigenomes used in transfection contained a nonviral extension of three nucleotides, GGG, on the 5' (leader) end contributed by the T7 promoter. The termini of the recovered minigenomes were examined for five mutants by RNA circularization followed by cDNA synthesis, amplification, cloning, and sequencing. Unexpectedly, each recovered minigenome contained the complement of this nonviral extension on the 3' (leader) end, showing that it had been faithfully copied and maintained during RNA replication and passage. The nonviral trinucleotide did not appear to affect the activity of the template.
 ...
PMID:RNA replication by a respiratory syncytial virus RNA analog does not obey the rule of six and retains a nonviral trinucleotide extension at the leader end. 876 15

The 2A region of the foot-and-mouth disease virus (FMDV) polyprotein is 18 amino acids in length, and 2A self-cleavage site (2A/2B) contains a conserved amino acid motif G2A/P2B. To investigate the synonymous codon usage for Glycine at the 2A/2B cleavage site of FMDV, 66 2A/2B1 nucleotide sequences were aligned and found that the synonymous codon usage of G2A is conserved and GGG was the most frequently used. To examine the role of synonymous codons for G2A in self-cleavage efficiency of 2A/2B, recombinant constructs which contains the chloramphenicol acetyltransferase protein (CAT) and enhanced green fluorescent protein (EGFP) linked by the FMDV 2A sequence with four synonymous codons for G2A were produced. The activities of all the F2As based plasmids were determined in CHO cells. The results showed that the synonymous codon usage patterns for G2A at the cleavage site (2A/2B) have no effect on the cleavage efficiency. This suggests that the synonymous codon usage of 2A peptide has no effect on the cleavage efficiency of FMDV 2A element.
...
PMID:The silent point mutations at the cleavage site of 2A/2B have no effect on the self-cleavage activity of 2A of foot-and-mouth disease virus. 2515 85