Cell Cycle p21, Depression, and Neurogenesis and in the Hippocampus

This is somewhat of a followup post. What’s really cool about this paper (to Sci, anyway), is that it brings two different areas that she’s been interested in into one cool glob of SCIENCE. And it helps to explain many of the questions that Sci got in response to two of the papers she has blogged about recently.
They are these:
1) The Incredible Healing Mouse: Bedelbeava et al. “Lack of p21 expression links cell cycle control and appendage regeneration in mice” Proceeding of the National Academy of Sciences, 2010.
2) The neurogenesis theory of depression and a little guy called CREB: Gur et al. “cAMP Response Element-Binding Protein Deficiency Allows for Increased Neurogenesis and a Rapid Onset of Antidepressant Response” The Journal of Neuroscience, 2007.
And NOW, behold their MUTANT OFFSPRING:
ResearchBlogging.org Pechnick et al. “p21 restricts neuronal proliferation in the subgranular zone of the dentate gyrus of the hippocampus” PNAS, 2008.
Well ok, technically it isn’t a mutant offspring, because this paper was BEFORE the first paper and after the second. So I guess it’s a stepchild. Or a sibling. Or just the results of how Sci was searching PubMed that day.
Let’s start with some background.

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