The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Phosphorylation at clustered -Ser-Pro-X-Lys/Arg- motifs in sperm-specific histones H1 and H2B.

Sea urchin sperm-specific histones H1 and H2B have distinctive N-terminal, and in the case of H1 also C-terminal, domains containing repeats of a basic motif (-Ser-Pro-Lys/Arg-Lys/Arg- or a closely related sequence). The histones in spermatids (the precursors of sperm) are phosphorylated, and the unphosphorylated histones of mature sperm are rephosphorylated upon fertilization. These changes correlate with finely tuned changes in chromatin packing in the nucleus, and the domains responsible are evidently the N-terminal domains. We show that in spermatids there are six tandemly repeated phosphorylation sites in the N-terminal domain of H1 (a typical cAMP dependent protein kinase site is not phosphorylated) and that H2B is phosphorylated in the N-terminal domain at two or three sites in the case of H2B1 and four sites in H2B2. The consensus sequence for phosphorylation is -Ser-Pro-X-Lys/Arg-, where X is Thr, Gln, Lys or Arg. There is an additional phosphorylated site in the C-terminal domain of H1 but most (or possibly all) copies of the consensus motif, which are here dispersed, are not phosphorylated. The negative charge introduced upon phosphorylation would be expected to weaken or abolish electrostatic interaction with DNA of this motif, which also occurs, and is phosphorylated, in somatic H1s.[1]

References

 
WikiGenes - Universities