Transporters, Receptors, and other vocab Flashcards
Science is basically learning a new language. This is the molecular/genetic/cellular stuff - current to mid 2015
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
GLUT4
Glucose transporter 4. Found in skeletal muscle. Insulin dependent.
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
MuRF1
Muscle ring finger protein-1, an E3 ubiquitin ligase
Cortisol indirectly upregulates MuRF1 to increase proteolysis
(From Dr. Pak: In diseases that suppress insulin/IGF-1 signaling, the PI3-K/Akt pathway is depressed, leading to decreased protein synthesis and FoxO phosphorylation. This allows FoxO to stimulate the expression of the E3 enzymes atrogin-1 and muscle ring finger-1 (MuRF-1) and protein degradation.)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
NF-KB
Transcription factor for a number of inflammatory genes; exists constitutively in the cytosol bound to its inhibitor, I-KB (glucocorticoids bind/inactivate NF-KB; up regulate I-KB)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
11-DOC
11-Deoxycorticosterone. Mineralocorticoid precursor of aldosterone. If in excess (for example if missing an enzyme further into the pathway), may bind MR receptors producing the same physiological effects as aldosterone - sodium/water retention, probably also HTN
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
11ß-HSD1
11-ß hydroxysteroid dehydrogenase 1; present in cells with glucocorticoid receptors, converts cortisone to cortisol (active form)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
11ß-HSD2
11ß hydroxysteroid dehydrogenase 2. In cells with mineralocorticoid receptors (especially kidney distal convoluted tubule), converts cortisol to cortisone (inactive; freely diffuses out of the cell)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
DHEA
5-dehydroepiandrosterone. Weak androgen produced by adrenal zona reticularis; precursor for testosterone/E2.
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
StAR
Steroid Acute Regulatory Protein. Transports free cholesterol from outer mitochondrial membrane to inner mitochondrial membrane. RATE LIMITING STEP FOR STEROID BIOSYNTHESIS. Regulated by ACTH
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
Cyp11A1
Cyp11A1 is the gene coding for P450scc, or desmolase. Desmolase converts cholesterol to pregnenolone, the primary precursor for all steroid hormones, by cleaving off a side chain of cholesterol (activity increased as ACTH levels increase). Expressed in inner mitochondrial membrane of all three layers of adrenal cortex.
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CYP21A2
P450c21; 21α hydroxylase. Expressed in adrenal cortex zona glomerulosa and fasciculata
Converts progesterone to 11-deoxycorticosterone (11-DOC) in z. glomerulosa
Converts 17(OH)-progesterone to 11-deoxycortisol in z. fasciculata
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CYP11B2
(one gene product with three activities; give common name of gene product as well as common name of each activity)
P450aldo; Aldosterone synthase. Present in Zona glomerulosa of adrenal cortex
(do not confuse with CYP11B1 gene product, which functions in the cortisol biosynthetic pathway)
- 11-hydroxylase converts 11-DOC to corticosterone.
- 18-hydroxylase converts corticosterone to 18(OH)-corticosterone.
- 18-oxidase converts 18(OH)-corticosterone.to aldosterone (NOT cortisol!)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CYP17
P450c17; 17-hydroxylase. Present in zona fasciculata and reticularis of adrenal medulla.
Converts progesterone to 17(OH)-progesterone in cortisol biosynthetic pathway in z. fasciculata
Converts pregnenolone to 17(OH)-pregnenolone in DHEA biosynthetic pathway in z. reticularis
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CYP11B1
P450c11; 11-hydroxylase
not to be confused with a gene product of the same common names, CYP11B2/aldosterone synthase!
Converts 11-deoxycortisol (NOT 11-DOC) to cortisol in cortisol biosynthetic pathway. Expressed in zona fasciculata.
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
COMT
catechol-O-methyltransferase
Methylates catecholamines for clearance.
End product of breakdown: vanyllilmandelic acid
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
MAO
monoamine oxidase
Deaminates catecholamines for clearance
Eventual end product: vanillylmendelic acid
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
NIS
Sodium-iodide symporter. Found on basolateral membrane of thyroid follicular epithelial cell. Together with thyroid peroxidase (TPO; forms iodine), thyroid iodide “trap”
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
Type I deiodinase
Outer and inner ring deiodinase.
Found in liver, kidney, skeletal muscle, thyroid
Primary source of T3 in circulation
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
Type II deiodinase
Outer ring deiodinase only (activates T4 → T3)
Found in brain, pituitary, placenta, cardiac muscle
**Also the thyroid “sensor” in the pituitary
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
Type III deiodinase
Inner ring deiodinase only (inactivating enzyme)
Found in brain, placenta, skin
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
TBG
Thyroid binding globulin. Carries 70% of T4/T3 in circulation
394aa glycoprotein; Serpin family (but not a protease inhibitor)
Circulating protein, synthesized in liver
Hepatitis, increased [estrogen] increase TBG; Nephrotic syndrome, steroids decrease TBG; neither affects free T4/T3
**Unique: Reversibly binds T4 (compare to other steroid binding globulins)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
TG
Thyroglobulin
Found exclusively in thyroid; used for T3/T4 synthesis. Stored in colloid and makes up the bulk of colloid mass.
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
TTR
Transthyretin. A secondary thyroid binding protein. Transports about 10% of T4/T3 in circulation
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
THR
Thyroid hormone receptor
Nuclear receptor
Forms heterodimer with retinoic acid
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
PTHrP
Parathyroid hormone related peptide
Highly analagous to N-terminal (active; 1-34) fragment of PTH
Has some normal functions, but most known for calcium wasting from bone / hypercalcemia when secreted to excess by a neoplasm [commonly renal, head/neck, lymphoma, bladder]
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
PTH1R
Primary PTH receptor
Located in osteoblasts and kidney
Binds both 1-34 and 1-84 fragment as well as PTHrP
Gs and Gq activity - cAMP AND IP3/DAG
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
PTH2R
Secondary parathyroid hormone receptor. Not especially important in humans (that we know of)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
RANKL
RANK - ligand.
Secreted by osteoblasts. Stimulates osteoclasts, promotes bone remodeling.
Inhibited by OPG
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
OPG
Osteoprotegerin.
Antagonist/soluble decoy for RANKL (binds and prevents from activating RANK - decreases osteoclast activity
Stimulated by PTH, estrogens; inhibited by cortisol
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CYP1α
1α-hydroxylase.
Expressed in renal cells of proximal tubule.
Converts 25-hydroxycholecalciferol (25(OH)-D3) to active form of Vitamin D: 1,25-dihydroxycholecalciferol (1,25(OH)-D3)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CaSR
Calcium-sensing Receptor
Located in chief cells, kidney tubules, C cells
Binds ionized calcium; represses PTH at promoter level; stimulates PTH degradation
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
VDR
Vitamin D receptor.
Inhibits PTH synthesis at promoter level
Stimulates CaSR gene transcription
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
GLUT1
Insulin independent glucose transporter; uptake under basal conditions
Expressed in brain, vasculature, erythrocytes, SkM, fat, heart (minor in heart)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
GLUT2
Insulin independent glucose transporter
LOW AFFINITY
Expressed in liver, pancreatic beta cells, kidney, small intestine
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
GLUT3
Glucose transporter
Insulin independent
Primary glucose transporter in brain/neural tissue
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
GLUT5
Fructose transporter
Expressed in small intestine, spermatozoa
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
IgG
Predominant antibody induced in secondary immune response
Only Ig to cross placenta
Complement fixation variable based on subtype
gamma chain. MW 150 kD
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
SReBP-1C
Steroid Regulator Binding Protein 1C
Promotes triglyceride synthesis
Activates glucokinase, promoting glucose “trapping” in cells
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
PPARγ
Peroxisome proliferator-activated receptor gamma (or glitazone receptor)
Nuclear transcription factor
Regulates TG storage and adipocyte differentiation
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
PAMPS
Pathogen-associated Molecular Patterns
“molecular danger pattern” specific to a pathogen.
Sensed by pattern recognition receptors (TLRs, etc) on innate immune cells
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
DAMPS
Damage associated molecular patterns
Recognized by pattern recognition receptors on innate cells (TLRs etc)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
TLR
TOLL-like receptor.
Family of transmembrane pattern recognition receptors (PRR) expressed on phagocytes
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
RLR
RIG-I helicase-like receptor
Retinoic acid inducible gene receptor
Family of soluble intracytoplasmic pattern recognition receptors (PRR) expressed by phagocytes
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
NLR
NOD-like receptor
Nucleotide binding domain and leucine rich repeating receptor
Family of soluble intracytoplasmic pattern recognition receptors (PRR) expressed by phagocytes
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CLR
C-type lectin receptor
Family of transmembrane pattern recognition receptors (PRR) expressed on phagocytes
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
IgA
Predominant Ig in external secretions
In secretions, exists primarily as a dimer; circulates as a monomer
Complement fixation by alternative pathway
alpha heavy chain. MW 160 kD
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
IgM
Predominant Ab induced in primary response; also expressed as a monomer on B cells (part of BCR)
Low avidity, high affinity (due to 10 epitope binding sites) makes it ideal for a first responder
Effective complement fixation - classical pathway
mu heavy chain. (pentameric) MW 900 kD
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
IgD
found on surface of B cells
delta heavy chain
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
IgE
primary Ig of allergic reactions
2 Fc receptors on epsilon heavy chain. MW 190 kD
Heavily glycosylated
Binds with very high (20K x IgG) affinity to its FcR
Normal response to parasites
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
FcR
Fc receptor
Ig-heavy-chain-subtype-specific-Fc-region receptor found on the surfaces of macrophages, neutrophils, NK cells, eosinophils, basophils, and mast cells.
Cross-linking of receptors activates cells
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
atrogin-1
An E3 ubiquitin ligase. Cortisol indirectly upregulates atrogin-1 to increase proteolysis.
(From Dr. Pak: In diseases that suppress insulin/IGF-1 signaling, the PI3-K/Akt pathway is depressed, leading to decreased protein synthesis and FoxO phosphorylation. This allows FoxO to stimulate the expression of the E3 enzymes atrogin-1 and muscle ring finger-1 (MuRF-1) and protein degradation.)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
ITAM
immunoreceptor tyrosine-based activation motif
it’s a motif that exists in the tails of certain receptors of the immune system. [The tyrosine residues of the motif are phosphorylated and form docking sites for other proteins in the signaling cascade]
With regard to the binding of an FcR on a phagocyte, this creates the intracellular signal to phagocytose the antigen
high affinity - activated at low levels of immune complexes
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
ITIM
immunoreceptor tyrosine based inhibitory motif
similar to an ITAM, it is a highly conserved aa sequence found on the tails of immune cells. When the receptor binds ligand, the tyrosines are phosphorylated and serve as a docking site for further intracellular signaling proteins
Important regulatory mechanism for B cells - low affinity - activtated when there are very high levels of immune complex to shut off antibody production
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
B7
(aka CD80 and CD86)
co-stimulatory molecule expressed on the surface of activated Dendritic cells
interfaces with CD28 on T lymphocytes
major signature of an activated APC that has taken up a microbial pathogen; expressed on BC’s ONLY AFTER uptake of an antigen specific to to its BCR
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
TAP (1 and 2)
Transporters Associated with Antigen Processing (1 and 2)
sole function is to push degraded proteins into ER for presentation by MHC-1
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
calnexin
ER chaperone
(MHC-I is bound to calnexin until associated with β2-microglobulin; then passed to calreticulin/ERp57)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
ERp57
ER chaperone
(along with calreticulin, receives MHC-1 after binding of β2microglobulin)
associates with TAP via tapasin
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
calreticulin
ER chaperone
along with ERp57, receives MHC-1 from calnexin after binding of β2-microglobulin
the complex associates with TAP via tapasin
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
ERAAP
endoplasmic reticulum aminopeptidase associated with antigen processing
expressed in ER. trims proteins pumped into ER by TAP, for presentation on MHC-I
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
tapasin
ER protein
associates TAP with the calreticulin/ERp57/MHC-I complex for peptide delivery
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
Ii
invariant chain
MHC-II are transported from ER to endosomes with Ii occupying the peptide cleft
Ii cleaved by acidification leaving CLIP
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CLIP
class II-associated invariant chain peptide
remnant of Ii that remains in MHC-II binding groove after acidification of storage endosome
thought to be the only thing expressed in MHC-II cleft under steady state conditions
HLA-DM causes dissociation and allows other peptides to bind
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
HLA-DM
binds MHC-II-CLIP complex in endosome and releases CLIP, allowing antigenic peptides to find binding cleft
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CD28
costimulatory molecule expressed on naive TC’s
complex with B7 on APC to activate cell
(secondary signal to antigen/MHC-II recognition - and remember, these naive T’s are recognizing MHC-II, so whatever subset they evolve into, they are already CD3+/CD4+)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CD40
expressed on APC’s that have taken up “something weird” that isn’t a microbe - instead of B7
interfaces with CD40L on CD4’s to induce expression of B7 on the APC, which can then interface with CD28)
(extra step in the activation of the T cell)
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CD40L
expressed on the surface of TC’s that recognize “something” in an MHC-II of an APC (but the APC lacks B7 because the “something” isn’t a microbe)
interfaces with CD40 on the APC if the APC thinks it’s “weird” too
CD40/CD40L interaction stimulates the production of B7 which provides the costimulatory signal to the T cell
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
CD34
marker for HSC’s
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
Notch
receptor expressed on HSC’s in thymus
DL-1/4 binding (Notch Signaling) from TEC’s (DL=delta ligand) commits the cell to T/NK lineage
if notch signaling continues long enough, HSC commits to NK lineage
Give the common name of the protein or gene product, its action, important regulatory factors (if applicable) and tissue specificity (if applicable)
DL-1/DL-4
delta-ligand 1 and 4
expressed on TEC’s.
binds Notch receptor on HSC’s to signal commitment to TC lineage
long enough Notch signaling commits to NK cell
