There are RNA polymerase crystal structures that provide considerable insight into how the enzyme retains contact with its substrate while breaking and remaking bonds in the process of the nucleotide addition cycle and undergoing translocation by a Brownian ratchet mechanism.

TLS Online TPP Program

#Id: 5055

#Unit 3. Fundamental Processes

DnaA then acts at three A-T–rich 13-bp tandem repeats located on the left side of oriC.

TLS Online TPP Program

#Id: 1991

#Unit 3. Fundamental Processes

Polyadenylation requires a protein complex that contains a specificity factor, an endonuclease, and poly(A) polymerase.

 

TLS Online TPP Program

#Id: 9619

#Unit 4. Cell Communication and Cell Signaling

HER2 (mouse Erb-B2), cannot bind any ligand, it can form a heterodimer with ligand-activated HER1, HER3, or HER4 (Erb-B1, 3, or 4)

TLS Online TPP Program

#Id: 10239

#Unit 6. System Physiology – Plant

ABA was originally thought to induce abscission, however, abscission is regulated by ethylene rather than ABA.

TLS Online TPP Program

#Id: 8770

#Unit 1. Molecules and their Interaction Relevant to Biology