Estrogens inhibit osteoclastic activity in the bones and therefore stimulate bone growth.

TLS Online TPP Program

#Id: 7799

#Unit 2. Cellular Organization

Most mRNAs Are Exported from the Nucleus by a Ran-Independent Mechanism

TLS Online TPP Program

#Id: 7800

#Unit 2. Cellular Organization

The principal nuclear transport receptor of mRNPs out of the nucleus is :

A. mRNP exporter

B. Nuclear export factor 1 (NXF1)

C. Nuclear export transporter 1 (NXT1)

TLS Online TPP Program

#Id: 7801

#Unit 2. Cellular Organization

An RNA helicase (Dbp5) located on the cytoplasmic side of the NPC removes NXF1 and NXT1 from the mRNA in a reaction that is powered by ATP hydrolysis.

TLS Online TPP Program

#Id: 7802

#Unit 2. Cellular Organization

Free NXF1 and NXT1 proteins are recycled back into the nucleus by the Ran-dependent import process.

TLS Online TPP Program

#Id: 7803

#Unit 2. Cellular Organization

TLS Online TPP Program

#Id: 7837

#Unit 2. Cellular Organization

The direction of the transport processes depends on the localization of the Ran-GEF predominantly in the nucleoplasm and the Ran-GAP predominantly in the cytoplasm