BTG1

Protein BTG1 is a is_associated_with::protein that in humans is encoded by the BTG1 is_associated_with::gene.

Function
The BTG1 gene locus has been shown to be involved in a t(8;12)(q24;q22) is_associated_with::chromosomal translocation in a case of is_associated_with::B-cell chronic lymphocytic leukemia. It is a member of a family of antiproliferative genes. BTG1 expression is maximal in the G0/G1 phases of the is_associated_with::cell cycle and downregulated when cells progressed through G1. It negatively regulates is_associated_with::cell proliferation.

Interactions
BTG1 has been shown to interact with:
 * is_associated_with::CNOT7,
 * is_associated_with::CNOT8,
 * is_associated_with::HOXB9, and
 * is_associated_with::PRMT1.

Clinical relevance
Recurrent mutations in this gene have been associated to cases of is_associated_with::diffuse large B-cell lymphoma.

Maintenance of adult neural stem cells
Recent data, obtained in a new model of mouse lacking the BTG1 gene, indicate that BTG1 is essential for the proliferation and expansion of stem cells in the adult neurogenic niches, i.e. the dentate gyrus and subventricular zone. In particular, BTG1 keeps adult neural stem cells in quiescence, preserving the neural stem cells pool from depletion; in fact, in absence of BTG1, the stem and progenitor cells initially hyper proliferate and then in the longer period loose the ability to proliferate and expand (see for review: ). Other recent data indicate that physical exercise can fully reconstitute the proliferative defect of stem cells that follows the ablation of the BTG1 gene, suggesting that the pool of neural stem cells maintains a hidden form of plasticity which is tightly controlled by BTG1; hence, BTG1 might prevent the depletion of stem cells in the presence of strong neurogenic stimuli or of neural degenerative stimuli.

The closest homolog of BTG1 is BTG2, which also controls the proliferation and differentiation of adult neural stem cells; the role of BTG2, however, appears to differ from that of BTG1 being probably more relevant in controlling the terminal differentiation of neural stem and progenitor cells in the adult neurogenic niches.