The Guardian Angel

The Guardian Angel of CPR

Guardian Angel: Patient-Centered Health Information Systems

DNA repair: PARP –  another guardian angel?

Cell lines and mice defective in poly(ADP-ribose) polymerase (PARP) have elevated spontaneous genetic rearrangements and abnormal responses to stresses. These results may be explained by an altered response to damage induced by free radicals, and suggest that PARP limits genomic instability from such damage.

NANOS: a germline stem cell's Guardian Angel.

NANOS is known to be required for germline cell development in a variety of animal species and for the maintenance of germline stem cells in Drosophila. The recent study by Sada et al. has demonstrated that NANOS2, one of the three mammalian homologues, is required intrinsically for maintaining adult mouse spermatogonial stem cell self-renewal.

Growth Control: p53, the Guardian Angel of Compensatory Proliferation

Compensatory growth, or regeneration, is used to replace damaged tissue during animal development. Recent work has revealed a new role for Drosophila p53 in the compensatory proliferation of cells that are needed to repair damaged tissues, a role that requires the non-apoptotic function of the caspase protease Dronc.