- inaD signaling complex
A complex of proteins that are involved in phototransduction and attached to the transient receptor potential (TRP) channel. The protein connections are mediated through inaD.
- transcriptional attenuation by ribosome
A type of transcriptional regulation at the level of early termination. This process can occur only in prokaryotes, where transcription of an operon into messenger RNA and translation of that mRNA into polypeptides occur simultaneously. The general principle is that alternative mRNA secondary structures occur under different physiological conditions such as available amount of a particular amino acid. One set of conditions favors early termination of transcription. In the classic example of the trp biosynthesis operon, translation of the gene for a short, trp-containing polypeptide called the trp operon leader peptide pauses either at a trp codon (if tryptophan is scarce) or the stop codon (if trp is readily available). In the former situation transcription continues, but in the latter a Rho-independent terminator forms and reduces, or attenuates, expression of the tryptophan biosynthesis genes. Although the polypeptides encoded by leader peptide genes appear not to be stable once their translation is complete, it is suggested by recent studies that their nascent polypeptide chains interact specifically with ribosomes, specific uncharged tRNAs, or other cellular components to inhibit release at the stop codon and improve the function of transcriptional attenuation as a regulatory switch.
- ligand-activated transcription factor activity
A DNA-binding transcription factor activity regulated by binding to a ligand and that modulates the transcription of specific genes and gene sets. Examples include the lac and trp repressors in E.coli and steroid hormone receptors.
- obsolete endopeptidase Clp activity
OBSOLETE. Catalysis of the hydrolysis of proteins to small peptides in the presence of ATP and magnesium. Alpha-casein is the usual test substrate. In the absence of ATP, only oligopeptides shorter than five residues are cleaved, for example, succinyl-Leu-Tyr-NHMec which is cleaved at the Tyr-NHMec bond, and Leu-Tyr-Leu-Tyr-Trp which is cleaved at the second Leu-Typ bond (cleavage of the Tyr-Leu and Tyr-Trp bonds also occurs).
- NatC complex
A conserved complex that catalyzes the transfer of an acetyl group to the N-terminal residue of a protein acceptor molecule that has a Met-Ile, Met-Leu, Met-Trp, or Met-Phe N-terminus. In Saccharomyces the complex includes Mak3p, Mak10p, and Mak31p.