Cell Signaling and Protein Domains Quiz

<p>Protein kinase domain (D)</p> Signup and view all the answers

<p>Both domains have different structures but bind the same type of target. (C)</p> Signup and view all the answers

<p>As signals to either activate or deactivate signaling pathways. (D)</p> Signup and view all the answers

<p>It dissociates into active catalytic monomers. (C)</p> Signup and view all the answers

<p>Most proteins contain at least two structural domains. (D)</p> Signup and view all the answers

<p>Protein phosphatase domain (B)</p> Signup and view all the answers

<p>Enabling communication between proteins (A)</p> Signup and view all the answers

<p>Binding of a ligand to its cognate receptor (B)</p> Signup and view all the answers

<p>Signal amplification (D)</p> Signup and view all the answers

<p>They assist in the specific binding and interaction with other proteins. (C)</p> Signup and view all the answers

<p>To enhance the specificity and efficiency of signal transmission. (D)</p> Signup and view all the answers

<p>They maintain signal specificity until the final target is reached. (B)</p> Signup and view all the answers

<p>They are tightly controlled and restricted to authorized partners. (A)</p> Signup and view all the answers

<p>It induces structural changes leading to signal initiation. (D)</p> Signup and view all the answers

<p>It ensures that signals only affect appropriate target components. (A)</p> Signup and view all the answers

<p>Include at least two prolines in a PxxP motif (D)</p> Signup and view all the answers

<p>Grb2 (D)</p> Signup and view all the answers

<p>PTB domains (A)</p> Signup and view all the answers

<p>Interaction with acidic phospholipid head groups (A)</p> Signup and view all the answers

<p>Regulating fundamental cellular processes (B)</p> Signup and view all the answers

<p>Akt (A)</p> Signup and view all the answers

<p>Open active conformation (A)</p> Signup and view all the answers

<p>EF-hand motifs (C)</p> Signup and view all the answers

<p>To recognize and bind other signaling molecules (C)</p> Signup and view all the answers

<p>PSD-95 (B)</p> Signup and view all the answers

<p>Presence of PDZ, SH3, and GUK domains (C)</p> Signup and view all the answers

<p>To enhance efficiency and specificity of cellular pathways (C)</p> Signup and view all the answers

<p>InaD (D)</p> Signup and view all the answers

<p>SH2 domain (D)</p> Signup and view all the answers

<p>Membrane-Associated Guanylate Kinases (A)</p> Signup and view all the answers

<p>NHERF (B)</p> Signup and view all the answers

<p>Anchors protein kinase A for receptor phosphorylation (A)</p> Signup and view all the answers

<p>β-arrestin (D)</p> Signup and view all the answers

<p>JAKs (A)</p> Signup and view all the answers

<p>Through dimerization and translocation to the nucleus (A)</p> Signup and view all the answers

<p>Cytokine receptors lack intrinsic catalytic domains (D)</p> Signup and view all the answers

<p>Binds to non-PDZ based scaffold proteins (A)</p> Signup and view all the answers

<p>SH2 domain (C)</p> Signup and view all the answers

<p>JAK1 (A)</p> Signup and view all the answers

The process by which cells receive and respond to signals from their environment.

Proteins that play a key role in receiving, transmitting, and amplifying signals within cells.

Specific regions within signaling proteins that allow them to interact with other proteins and participate in signal transduction.

The initial step in signal transduction where a signaling molecule (ligand) binds to its specific receptor protein on the cell surface.

The process where signaling proteins interact with each other, allowing signals to be passed along in a relay.

A process where a phosphate group is added to a protein, often modifying its activity and allowing it to transmit a signal.

Proteins that act as platforms for other proteins to assemble, enhancing efficiency and specificity of signal transduction pathways.

The process where a signal is transferred from one protein to another, ensuring the signal is transmitted efficiently and without loss.

Regions within proteins that have specific structures and perform particular functions during interactions.

A process where a protein kinase adds a phosphate group to a protein, changing its activity.

Domains that specifically bind to phosphorylated tyrosine residues (p~Tyr).

Two domains with the same structure might have different functionalities, showing the complexity of protein function.

A structural domain that performs enzymatic activity, often by binding to specific substrates and facilitating chemical reactions.

A catalytic domain that adds phosphate groups to other proteins (phosphorylation), often regulating their activity.

A catalytic domain that removes phosphate groups from proteins (dephosphorylation), reversing the action of kinases.

Mutations can alter the structure or function of a protein domain by:

• Changing the sequence of amino acids within the domain.
• Changing the splicing pattern, affecting which exons are included in the final protein.
• Adding or removing sections of the domain (insertion, deletion, duplication).

A protein interaction domain that binds to short motifs containing proline-rich sequences, typically with 8–10 residues including at least two prolines in a PxxP motif.

A sequence of amino acids rich in proline residues, often containing the PxxP motif, and recognized by SH3 domains.

SH3 domains have a hydrophobic binding surface, which means they interact with non-polar molecules.

A domain that binds to phosphotyrosine residues (N-P-X-pY) but recognizes sequences different from those recognized by SH2 domains.

PhosphoTyrosine Binding domains can bind to acidic phospholipid head groups, such as those found in phosphoinositides, which are commonly found in membranes.

A domain that binds to phosphoinositides and the βγ-subunits of Gi-proteins, often found in membranes of organelles and the plasma membrane.

There are several, including SH2, SH3, PTB, PH, EF-hand, C2, zinc finger, and protein kinase domains.

Scaffold proteins that recognize and bind to specific amino acid sequences (PDZ domains) on other proteins.

Scaffold proteins that don't rely on PDZ domains to interact with other proteins. Instead, they use other types of protein-protein interactions.

A non-PDZ-based scaffold protein involved in regulating the activity of protein kinase A (PKA).

A non-PDZ-based scaffold protein involved in signaling pathways downstream of cytokine receptors.

A non-PDZ-based scaffold protein that interacts with phosphorylated G protein-coupled receptors (GPCRs), interfering with their signal.

A signaling pathway involving cytokine receptors, JAK kinases, and STAT transcription factors.

Receptors that can bind both PDZ-based and non-PDZ-based scaffold proteins, influencing signaling pathways.

A short sequence of amino acids found on signaling proteins that binds to a PDZ domain on another protein. This interaction is important for signaling protein assembly.

Scaffold proteins are proteins that enhance the efficiency of signal transduction pathways. They do this by bringing together multiple signaling proteins and organizing them into protein complexes.

PSD-95 is a PDZ-based scaffold protein that is important in the brain. It helps organize proteins at the synapse, a junction between neurons, which is essential for communication between nerve cells.

InaD is a scaffold protein in the Drosophila melanogaster phototransduction cascade. It helps organize proteins that are involved in the sensing of light.

MAGUK proteins are scaffold proteins important in signaling. They have multiple domains, including PDZ, SH3, and GUK, which allow them to interact with other proteins and organize signaling complexes.

MAGUK stands for Membrane-Associated Guanylate Kinases.

MAGUK proteins are characterized by having three important domains: a PDZ domain, an SH3 domain, and a GUK (guanylate kinase) domain. These domains are vital for their roles in signaling.