Disease relevance of Rps6kb2

• Here we show that overexpression of S6K1 induced a modest degree of hypertrophy, whereas overexpression of S6K2 resulted in no obvious cardiac phenotype [1].

High impact information on Rps6kb2

• This newly identified gene product, termed S6K2, is ubiquitously expressed and displays both mitogen-dependent and rapamycin-sensitive S6 kinase activity [2].
• More striking, in p70(s6k)/p85(s6k)-deficient mice, the S6K2 gene is up-regulated in all tissues examined, especially in thymus, a main target of rapamycin action [2].
• This is the first indication that S6K2 plays a role in IL-3-dependent cell proliferation [3].
• S6K2 is also activated in primary mouse bone marrow-derived mast cells upon IL-3 stimulation [3].
• In contrast, rapamycin decreased the phosphorylation of S6K2 and S6 in myotubes [4].

Biological context of Rps6kb2

• Analysis of S6 phosphorylation in the cytoplasm and nucleoli of cells derived from the distinct S6K genotypes suggests that both kinases are required for full S6 phosphorylation but that S6K2 may be more prevalent in contributing to this response [5].
• Deletion of the S6K1 gene in mouse cells led to an animal of reduced size and the identification of the S6K1 homolog, S6K2, whereas loss of dS6K function in Drosophila demonstrated its paramount importance in development and growth control [6].

Associations of Rps6kb2 with chemical compounds

• Although S6K1 phosphorylation was reduced in leucine-deprived myotubes, S6K2 and S6 phosphorylation were not affected [4].

Other interactions of Rps6kb2

• Compared to wild-type mice, S6K1(-/-) mice are significantly smaller, whereas S6K2(-/-) mice tend to be slightly larger [5].

References