Cell and Molec Neuro Final

Each synapse is a complex of three components including

presynaptic element, synaptic cleft, postsynaptic element

T/F: The DNA sequences encoding 5’ UTR exist in mature mRNA, but do not specify the protein sequence. The sequences encoding 5’ UTR and 3’ UTR are introns.

false

What is the first amino acid of each protein of eukaryotic cells?

methionine

All of the following is correct about DNA, EXCEPT:

adenine and guanine are pyrimidines

Upon action potential, which of the following are involved in activating c-Fos transciption?

1. Ca2+ is increased

2. CREB is phosphorylated

3. CBP is recruited

4. HDAC is removed

1,2,3,4

The asymmetric concentration gradient of Na+ and K+ across the membrane is maintained by the

Na+/K+ ATPase

T/F: The 3’ OH in ribose makes mRNA strands less stable than DNA strand

false

mRNA modification includes

1. 5’ Cap

2. 3’ polyA

3. RNA splicing

1,2,3

T/F: In proteins, amino acids are referred to as residues

true

GCaMP’s consist of a circularly permuted enhanced green fluorescent protein (EGFP), which is flanked on one side by calmodulin and the other side by M13. Which of the following is correct?

All the other three answers

Which of the following is present in RNA, but absent in DNA of a cell?

additional hydroxyl group

Which of the following glial cells are not present in the central nervous system?

schwann cells

Two cells, referred to as heating cells, are activated in response to temperature increases. Which experimental technique would be most appropriate for determining whether these cells direct animals to move toward or away from high temperatures?

optogenetics

The N terminus of a polypeptide has a free ___ group

NH3+

If you make a chimeric factor with the DNA binding element of an activator and a functional domain of a repressor, how will it behave?

it will act like a repressor

Which statement about ionic distributions in nerve cells is true?

sodium is higher outside cells than inside cells

Which RNA molecule is translated?

mRNA

To examine both excitatory synapses and inhibitory synapses in rat hippocampal neurons in culture, an anti-vGLUT1 antibody generated from mice and an anti-GAD65 antibody generated from rabbits were used for immunostaining. The available secondary antibodies include:

1. anti-mouse cy3

2. anti-rabbit cy3

3. anti-mouse cy5

4. anti-rabbit cy5

5. anti-mouse fitc

6. anti-rabbit fitc

Which pair of antibodies can you use?

1 and 6

S phase is dedicated to what action?

DNA synthesis

Radial glial cells can generate

neurons, astrocytes, oligodendrocytes, ependymal cells, B cells

Based on the genetic code table, which of the following is not a silent mutation?

UAC to UAA

T/F: when we perform optogenetics in mice, we don’t need to add retinal. this is because channelrhodopsin does not need retinal when activated in the mouse brain.

false

Na+/K+ pump hydrolyzes ___ as energy to pump ___ into the cell and ___ out of the cell.

ATP, 2 K+, 3 Na+

To examine both excitatory synapses and inhibitory synapses in rat hippocampal neurons in culture, immunostaining was performed. The available antibodies include:

1. anti-vglut 1 (mouse)

2. anti-vglut1 (rabbit)

3. anti-gad 65 (mouse)

4. anti-gad 65 (rabbit

Which two primary antibodies should you use?

1 and 4 or 2 and 3

Which of the following is correct about the central dogma of molecular biology?

Transcription happens in the nucleus

T/F: glial cells are exclusively present in CNS

false

Which of the following descriptions about epigenetic modifications is not correct?

Epigenetic modification does not change DNA sequence, thus is not heritable

Which of the following methods is most suitable for determining whether the protein TRPV1 is expressed on the cell membrane?

immunostaining

What are the three major regions in a typical neuron?

axon, dendrite, cell body

Halorhodopsin can be used to test if sweet neurons are NECESSARY for the attractive behavior of sugar

This is correct, because halorhodopsin can inactivate sweet neurons. If the attractive behavior to sugar diminishes in yellow light, it will indicate that sweet neurons are necessary for the attractive behavior.

T/F: In a cell cycle, interphase includes G1, S, and G2.

true

Acute stress, such as forced swimming, ____ the methylation of ___ in CpG islands at c-Fos promotor, which facilitates transcription.

decreases, C

T/F: in calcium imaging, higher fluorescence usually indicates higher neuronal activity

true

What is the expected charge, if any, on a histone that binds to DNA?

positive

Which of the following structures represents a peptide bond between adjacent amino acids?

A, bond is between the c terminal of one amino acid and the n terminal of the other amino acid

Upon stimulation, methylation of CpG islands in the c-fos promotor is

decreased, and this decrease can be repressed by methyl donors, such as SAM

To test whether bitter neurons are sufficient for aversion to bitter tastants, one should:

express channelrhodopsin in bitter neurons, if the animals avoid the light, it indicates that bitter neurons are sufficient for aversion to bitter tastants

Which of the following descriptions about B cells in SEZ is not correct?

B cells cannot renew themselves

T/F: biological cells are only composed of lipids

false

Which nucleotide in DNA is usually methylated?

C (cytosine)

T/F: both miRNA duplex and siRNA duplex guide RNA-induced silencing complex to target DNA

false

T/F: c-Fos may serve as a molecular marker for neuronal firing

true

Which statement is a common, defining feature of membrane-bound active transporters?

All are able to move at least one ion against its concentration gradient

Protein synthetic machinery includes:

1. miRNA

2. tRNA

3. ribosome

4. mRNA

2,3,4

T/F: Protein is synthesized from the C terminus

false

Which of the following is a correct order for cotranslational translocation?

1. the ribosome binds mRNA and translation starts

2. translation is slowed

3. translation continues

4. the signal sequence is recognized by recognized and bound by SRP

5. SRP binds to the SRP receptor

6. the ribosome is docked at translocon

7. the nascent peptide passes through translocon and into the ER lumon

1,4,2,5,6,7,3

T/F: neurofilaments play a role in determining axonal diameters

true

Which nucleotides do the binding blocks of microtubules, microfilaments, and neurofilaments bind?

GTP, ATP, no binding nucleotide

The main function of microglia include

both CNS maintenance and immune defense

Which of the following is TRUE about saltatory conduction?

Myelinated axons exhibit greater conduction velocity than non-myelinated axons

Which of the following cytoskeletons belong to intermediate filament?

1. tubulin

2. actin

3. neurofilament

4. glial fibrillary acidic protein

5. vimentin

3,4,5

Which is NOT a function of astrocytes?

Promote the birth of new neurons in cases of chemical or physical damage

____ anchors synaptic vesicles to microfilament and prevents them from moving to the presynaptic membrane

synapsin

Serotonin is removed from a synaptic cleft by

all of the other three

Metabotropic receptors are

coupled to ion channels via G-proteins

T/F: opioids can act on both presynaptic and postsynaptic effects to reduce/block the neurotransmission of pain signals

true

When GABA binds to ionotropic GABA receptor, ___ fluxes into neurons.

Cl-

Which statement about muscarinic acetylcholine receptors is true?

They are metabotropic receptors

For small molecule neurotransmitters, which of the following is NOT correct?

The precursor molecules are always synthesized in presynaptic terminals

All of the following are a chemical class of neurotransmitters except

nucleic acids

What phosphorylates the intracellular domains of receptor tyrosine kinases?

The other intracellular domains in the dimer

__ transports choline to presynaptic terminals

choline transporter

About PKA, which of the following is not correct?

PKA’s catalytic domain is responsible for removing phosphate groups from substrate proteins

Listed below are the events that make up NGF-mediated growth of sensory neurons:

1. TrkA receptor self phosphorylation

2. NGF-induced dimerization of membrane receptors

3. TrkA induction of the ras signaling pathway

which is the correct sequence of these events?

2,1,3

Which of the following is a role of D2 autoreceptors?

increase reuptake of dopamine

Which statement about a nicotinic acetylcholine receptor at the neuromuscular junction is accurate?

It has two binding sites, and binding of two molecules of acetylcholine, one to each site, is required to activate the receptor

The precursor of glycine neurotransmitter is

serine

Which second messenger signals the release of Ca2+ from the ER?

IP3

Precursors of peptide neurotransmitters are synthesized in the ___ and packed into vesicles in the ____

rough ER, trans-golgi network

___ catalyses acetyl coA and choline to form acetylcholine

choline acetyltransferase

Which of the following ions causes the presynaptic vesicles to fuse with the presynaptic membrane and releases a neurotransmitter into the synaptic area?

calcium

Which out of the following statements is true about G protein-coupled receptors?

the N-terminal chain is extracellular and the C-terminal chain is intracellular

For peptide neurotransmitters, which of the following is NOT correct?

neuropeptides are packaged into vesicles and transported along an axon and down to the synaptic terminal via dynein-activated axonal transport

You’re working on a new GCPR. A colleague studying a pathogenic bacterium has discovered that it secretes a toxin that interferes with signaling in response to your ligand. She wants to collaborate with you in determining how this toxin acts. You do a preliminary experiment in which you look at intracellular cAMP levels in untreated and toxin treated cells. Which of the following might be correct about how the toxin affects adenylyl cyclase activity?

If the GCPR activates Gas, the toxin might inhibit GTPase activity

About nitric oxide, which of the following is NOT correct?

NO synthase catalyzes the nucleotide, arginine, to nitric oxide and citrulline

T/F: adenosine may activate and inhibit adenylyl cyclase in postsynaptic neurons

true

There are four subunits in each of the following receptors except

nACHr

M1R, M3R, and M5R activate Gq, Gq then

activates PLC

Which of the following is not considered a classic neurotransmitter?

adenosine

Which of the following molecules are synthesized in vesicles?

1. pre-proenkephlin A

2. proenkephlin A

3. met-enkephlin

4. leu-enkephlin

3,4

Peptide neurotransmitters are often released

Together with nonpeptide transmitters

You’re working on a pair of newly identified GPCRs, GCPR-A and GPCR-B. You find that the binding of a ligand has opposite effects on adenylyl cyclase activity for each receptor. GPCR-A causes an increase in adenylyl cyclase activity, while GCPR-B causes a decrease in adenylyl cyclase activity. What type of G-protein may be activated by each receptor?

GPCR-A: Gas

GPCR-B: Gai

The presence of which compound or protein in a cell makes it quite likely that the cell is a GABAergic neuron?

Glutamic acid decarboxylase

T/F: the beta/gamma complex of G proteins can also transduce signals

true

__ is the vesicular transporter that loads glycine into synaptic vesicles

vesicular inhibitory amino acid transporter

About the difference between neuropeptides and small molecule neurotransmitters, which of the following is not correct?

Small molecule neurotransmitters are released upon action potentials, while neuropeptides are not released upon action potentials

About endocannabinoids, which of the following is NOT correct?

2-AG and AEA are released from the postsynapic neurons through exocytotic mechanisms

Which of the following about GPCR desensitization is not correct?

phosphorylation of GPCRs may cause receptor degradation by mitochondria

T/F: muscarinic M3 receptor signaling pathway has opposite effects on airway smooth muscle and vascular smooth muscle. this is because the M3 receptor couples to different subgroups of G proteins.

false

In astrocytes, ___ converts glutamate to glutamine

glutamine synthetase

Which neurotransmitter is NOT classified as an amino acid neurotransmitter?

glutaminase

T/F: Virtually all neuropeptides initiate their effects at ionotropic receptors

false

About metabotropic dopamine receptors, which of the following is NOT correct?

D2-like receptors often increase the excitability of the postsynaptic neuron

About mGluRs, which of the following is NOT correct?

the glutamate binding site, venus flytrap domain, is in the c-terminal extracellular part

Listed below are the individual events that make up the chemical synaptic transmission:

1. diffusion of transmitter across the synaptic cleft

2. depolarization of the presynaptic terminal

3. vesicle fusion with plasma membrane

4. opening of voltage-gated ion channels

5. activation of presynaptic, calcium-sensitive proteins

Which sequence represents the correct ordering of these events?

2,4,5,3,1

Which statement regarding neurotransmitter receptors is true?

Ionotropic receptors have immediate effects; metabotropic receptors produce long-term effects

To knock down a gene using RNAi techniques, which of the following components need to be introduced into the cell?

1. shRNA

2. RNA-induced silencing complex

3. dicer

1

Methylation of CpG islands ____ transcription and acetylation of histones ___ transcription.

inhibits, activates

T/F: The space between the presynaptic and postsynaptic elements is named the synaptic cleft

true

When membrane is depolarized, voltage sensors of voltage-gated K+ channels moves towards to ___ membrane surface because this membrane surface is ___ charged.

Intracellular, negatively