Mice lacking p27(super Kip1) display increased body size, multiple organ hyperplasia, retinal dysplasia, and pituitary tumors

Article Abstract:

Mice lacking the cyclin-dependent kinase (CDK) inhibitor p27(super Kip1) have a large body size, organ hyperplasia and spontaneous pituitary tumors. CDK2 activity increases ten folds in thymocytes lacking p27. The male mice are fertile while females are sterile due to improper ovarian development. The cellular layer pattern development is disrupted in the retinas. However, the lack of the protein has no effect on the inhibitory effect of transforming growth factor beta on the cell cycle or arrest of embryonic fibroblasts in the G1 phase.

Observations, Hyperplasia, Pituitary gland tumors, Pituitary tumors

---

Enhanced growth of mice lacking the cyclin-dependent kinase inhibitor function of p27(super Kip1)

Article Abstract:

The loss of the cyclin-dependent kinase-inhibitory activity of the p27 protein increases growth and produces nodular hyperplasia in the pituitary's intermediate lobe in mice. However, there is no increase in the amount of growth hormone or insulin-like growth factor I. Mutant female mice are sterile due to defective luteal cell-differentiation and disordered estrus cycle. The defects in the hypothalamic-pituitary-ovarian axis change cell proliferation and cause specific endocrine dysfunction.

Metabolic regulation, Growth, Growth (Physiology), Growth regulators, Enzyme inhibitors, Pituitary gland

---

Deletion of SHIP or SHP-1 reveals two distinct pathways for inhibitory signaling

Article Abstract:

An inositol polyphosphate 5'-phosphatase, SHIP, and a tyrosine phosphatase, SHP-1, play a key role in the modulation of immune receptor activation by inhibitory coreceptors. A study was conducted to examine the necessity, interaction or redundancy of these signaling molecules. The findings indicate that SHP-1-mediated inhibitory signaling prevents apoptosis while SHIP recruitment attenuates a proapoptotic signal initiated by FcgammaRIIB.

Cell death, Cell receptors, Immune response, Phosphatases

Similar abstracts:

• Abstracts: Denitrifying bacteria in the earthworm gastrointestinal tract and in vivo emission of nitrous oxide (N2O) by earthworms
• Abstracts: Genes responsible for nisin synthesis, regulation and immunity form a regulon of two operons and are induced by nisin in Lactococcus lactis N8
• Abstracts: Extracellular proteases produced by the Quorn myco-protein fungus Fusarium graminearum in batch and chemostat culture
• Abstracts: Demonstration of high-affinity Mn2+ uptake in Saccharomyces cerevisiae: specificity and kinetics. Mixed sulphate-reducing bacterial cultures for bioprecipitation of toxic metals: factorial and response-surface analysis of the effects of dilution rate, sulphate and substrate concentration
• Abstracts: Autocatalytic subunit processing couples active site formation in the 20S proteasome to completion of assembly

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.