chaperone

Apart from the name for a romantic bouncer, it is also a class of proteins necessary for folding. Although some proteins fold by themselves, many large and/or complex proteins need some help. Logically, there must be some proteins that self-assemble in the cell otherwise there would be a 'folder paradox'. That is, "who folds the folder"? (like who guards the guardians?).

Indeed, chaperones themselves are multisubunit structures whose components fold separately (or are folded by other chaperones? - bootstrapping). They have to be large enough to contain an unfolded protein, thought to be in a molten globule state, and pull it apart. This chaperone-globule complex has been observed for GroEl although not all chaperones catalyse folding this way. Global cell chaperones are non-specific, and take on any protein that comes their way. There are specific types, however, that fold only one family (eg steroid receptors).

There is some naming confusion, due to their origional name of 'heat shock proteins' (HSPs) and subsequent name divergence of chaperones to chaperonins! The HSP60 / GroEl / Thermosome type are called chaperonins while the others are HSP70 / Dnak / Bip ....

"A romantic bouncer," as The Alchemist puts it. A person, most commonly female and some years older than the people she is accompanying, who accompanies an unmarried heterosexual couple so that they will not have a chance to be alone together and do anything considered inappropriate or immoral for an unmarried couple to be doing.

A nearly obsolete concept now in most Western cultures, but extremely important in the past to protect a woman's reputation. For example, in the book Gone With The Wind, Scarlett O'Hara is gossiping with a friend about Rhett Butler and is told: " Well, this Mr. Butler took a Charleston girl out buggy riding. I never did know who she was, but I've got my suspicions. She couldn't have been very nice or she wouldn't have gone out with him in the late afternoon without a chaperon. And, my dear, they stayed out nearly all night and walked home finally, saying the horse had run away and smashed the buggy and they had gotten lost in the woods. And guess what—"

"I can't guess. Tell me," said Scarlett enthusiastically, hoping for the worst.

"He refused to marry her the next day!"