Chapter 9
Helix-Turn-Helix
Leucine Zipper
Helix-Loop-Helix
Zinc Finger Proteins
What are the motifs that bind to cis-regulatory sequences?
What is one of the most important characteristics of a lipid bilayer?
What is fluidity?
What is the name of a negatively charged ion?
What is an anion?
These are the two main types of membrane transport proteins that move substances across the cell membrane: one type moves molecules down their concentration gradient without energy, the other uses energy to move molecules against their gradient.
What are channels and transporters?
These two types of regulatory proteins control gene expression by either increasing transcription by helping the RNA polymerase bind to DNA or decreasing transcription by blocking RNA polymerase or recruiting inhibitory complexes.
What are activators and repressors?
What is used as a model to study membranes in experimental studies?
What is Liposomes?
Channels form what that extend across the lipid bilayer?
What is pores?
These membrane proteins move one substance across the membrane by using the energy stored in the movement of another substance, often linking the transport of ions like sodium to the transport of nutrients like glucose.
What are coupled transporters?
One of these operons is typically turned on by the presence of lactose and off when glucose is available, while the other is typically on by default but turned off when tryptophan is abundant.
What are the differences between the Trp operon and the Lac operon?
The fluidity of a lipid bilayer depends on what?
What is composition and temperature?
In what conformational state is the binding site exposed on the outside?
What is the outward-open state?
One of these channels opens or closes in response to changes in membrane potential, allowing ions to flow only when a threshold is reached, while the other is a broader category of membrane proteins that allow ions to pass either continuously or in response to various stimuli such as ligands, mechanical stress, or voltage changes.
What is the difference between voltage-gated channels and ion channels?
This is the process in which multiple transcriptional regulators bind to nearby DNA sites on or around a nucleosome in a coordinated manner, where the binding of one regulator increases the likelihood or stability of additional regulatory binding, often leading to enhanced control of gene expression.
What is the process of cooperative binding of regulators in the nucleosome?
What do plasma membranes contain that are activated by extracellular signals to cleave specific phospholipid molecules?
What is phospholipases?
What kind of cells contain symporters that are driver by the Sodium gradient across the plasma membrane?
What are the Intestinal and Kidney epithelial cells?
These are the three main types of passive transport across a cell membrane: one allows small nonpolar molecules to pass directly through the lipid bilayer, another uses protein channels to allow specific ions or water to flow through, and the third uses carrier proteins that bind a solute and change shape to move it across the membrane down its concentration gradient.
What is simple diffusion, channel-mediated diffusion, and transporter-mediated diffusion?
This biological concept describes a cell's ability to rapidly adjust which genes are expressed or silenced in response to environmental changes, stress signals, or developmental cues.
What is dynamic adaptability/changing of gene expression in response to internal and external stimulation?
What are abundant in the outer membranes of bacteria, mitochondria and chloroplasts?
What is Beta-Barrel proteins?
Cystosolic enzymes function best at what type of pH?
What is close-to-neutral pH (~7.2)?
This type of passive transport shows a linear increase in transport rate with increasing concentration gradient, because molecules move directly through the lipid bilayer. This type of passive transport shows a saturable, hyperbolic rate curve because it depends on membrane proteins that become fully occupied as solute concentration increases, reaching Vmax.
What are the differences in kinetics between simple diffusion and transporter-mediated diffusion?