Cell and Molecular Biology for Engineers: Exam 4 MasterSet

____ signaling is when cells communicate by binding directly to each other

juxtacrine

_____ signaling is when cells secrete ligands for nearby signaling

paracrine

______ are regulated small molecules that independently convey a signal between proteins in a cell, and they provide for both _____ (greatening the signal) and _____ (go rapidly where the signaling molecule cannot go)

second messengers, amplification, diffusion

______ makes cAMP

adenylyl cyclase

cAMP is broken down by _____

phosphodiesterase

cAMP activates _____ by binding its regulatory subunit and causing it to dissociate from its catalytic subunit

PKA

_____ cleaves PIP2 to create ___ and ____

PLC, DAG, IP3

The DAG-IP3 in the PLC/PKC pathway is as follows:

1) Ligands binds the _____ to activate the heterotrimeric G protein, which activates ______

2) This molecule then cleaves the PIP2 to yield ____ (1) and _____ (2)

3) (2) binds its receptor on the smooth ER to release Ca2+ into the _____

4) Ca2+ activates MLCK, which activates myosin contraction in smooth muscle cells

5) Ca2+ and ____ together activate ______ at the plasma membrane to release Ca2+ out of the cell and into the extracellular domain, stopping muscle contraction

6) Ca2+ is pumped back into the ER, and ___ gets phosphorylated

GPCR, PLC, DAG, IP3, cytosol, DAG, PKCs, DAG

The NO guanylyl cyclase pathway is as follows:

1) NO, a ____ agonist, is diffused to its target

2) ______ is generated

3) this molecule then activates _____

4) this molecule then phosphorylates substrates to inhibit cytosolic calcium concentrations and inhibit smooth muscle contraction

5) _____ cleaves cGMP back into GMP

GC, cGMP, PKG, PDE5

____ is a family of small GTPases that act as molecular switches in cells, and they are activated when GTP is bound and inactive when GDP is bound. ____ removes the GDP to allow for a new GTP to bind on turn it on. ____ accelerates the hydrolysis of the GTP to GDP to turn it off.

RAS, GEF, GAP

The G0 phase of the cell cycle is also sometimes referred to as _____

quiescence

_______ tag proteins with ubiquitin in chains (_______) so that the protein will be degraded by a _____.

Ubiquitin ligases, polyubiquitination, proteosome

the _______ checkpoint at the G2/M transition is what allows for mitosis to progress

Cdk1-Cyclin B Checkpoint

____ (control timing of cyclic variations in the concentrations of certian proteins) and _____ control cell growth/division

cyclins, checkpoints

When DNA damage is detected, ___ is phosphorylated so that it doesn’t degrade (normally it is ubiquitinated the moment it is produced), and it transcribes for p21 and proteins that lead to _____

p53, apoptosis