PARP1
Poly [ADP-ribose] polymerase 1 (PARP-1) also known as NAD+ ADP-ribosyltransferase 1 or poly[ADP-ribose] synthase 1 is an enzyme that in humans is encoded by the PARP1 gene.
Function
PARP1 works:
PARP1 is involved in:
PARP1 is activated by:
Role in DNA damage repair
PARP1 has a role in repair of single-stranded DNA (ssDNA) breaks. Knocking down intracellular PARP1 levels with siRNA or inhibiting PARP1 activity with small molecules reduces repair of ssDNA breaks. In the absence of PARP1, when these breaks are encountered during DNA replication, the replication fork stalls, and double-strand DNA (dsDNA) breaks accumulate. These dsDNA breaks are repaired via homologous recombination (HR) repair, a potentially error-free repair mechanism. For this reason, cells lacking PARP1 show a hyper-recombinagenic phenotype (e.g., an increased frequency of HR), which has also been observed in vivo in mice using the pun assay. Thus, if the HR pathway is functioning, PARP1 null mutants (cells without functioning PARP1) do not show an unhealthy phenotype, and in fact, PARP1 knockout mice show no negative phenotype and no increased incidence of tumor formation.
PARP
PARP may refer to:
Flatulence
Flatulence is defined in the medical literature as "flatus expelled through the anus" or the "quality or state of being flatulent", which is defined in turn as "marked by or affected with gases generated in the intestine or stomach; likely to cause digestive flatulence". The root of these words is from the Latin flatus – "a blowing, a breaking wind". Flatus is also the medical word for gas generated in the stomach or bowels. These standard definitions do not reflect the fact that a proportion of intestinal gas may be composed of swallowed environmental air, and hence flatus is not totally generated in the stomach or bowels. The scientific study of this area of medicine is termed flatology.
It is normal for humans to pass flatus through the rectum, although the volume and frequency may vary greatly between individuals. It is also normal for intestinal gas passed through the rectum to have a characteristic feculent smell, although this too may vary in concentration. Flatus is brought to the rectum by specialised contractions of the muscles in the intestines and colon. The noises commonly associated with flatulence ("Blowing a raspberry") are caused by the vibration of anal sphincters, and occasionally by the closed buttocks. Both the noise and smell associated with flatus leaving the anus can be sources of embarrassment or comedy in many cultures.
Podcasts:
