In Run-on transcription- the RNA polymerase that has already initiated transcription in vivo simply “runs on” or continues to elongate the same RNA chains. 

TLS Online TPP Program

#Id: 1312

#Unit 2. Cellular Organization

Cardiac glycosides (e.g., ouabain and digitalis) are a class of drugs that inhibits Na+-K+ ATPase.

TLS Online TPP Program

#Id: 1504

#Unit 2. Cellular Organization

Microtubules are polymers of the protein tubulin.

TLS Online TPP Program

#Id: 1505

#Unit 2. Cellular Organization

The tubulin subunit is a heterodimer formed from two closely related globular proteins called a-tubulin and b-tubulin.

TLS Online TPP Program

#Id: 1506

#Unit 2. Cellular Organization

a-tubulin and b-tubulin comprising 445–450 amino acids, which are tightly held together by noncovalent bonds.

TLS Online TPP Program

#Id: 1507

#Unit 2. Cellular Organization

Each α or β monomer has a binding site for one molecule of GTP.

TLS Online TPP Program

#Id: 1508

#Unit 2. Cellular Organization

The GTP that is bound to α-tubulin is physically trapped at the dimer interface and is never hydrolyzed.