X-Message-Number: 25562 From: Date: Sun, 16 Jan 2005 19:25:16 EST Subject: Re: oxidative stress and telomeres Physiological levels of O2 tend to be around 2-5% for a lot of cells, so it isn't surprising that a lot of cell types grow longer in culture at low O2 levels. Our lab has grown a lot of cell types at 2% O2 vs. 21%, and found that many will grow longer at the lower levels. It isn't always telomere shortening that cuts off division, though; it is more common that the P16 protein levels are elevated (presumably indicating DNA damage) and send the cells into early, non-telomere-related growth arrest (which we call "stasis" to differentiate it from true senescence). Content-Type: text/html; charset="US-ASCII" [ AUTOMATICALLY SKIPPING HTML ENCODING! ] Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=25562