Biochem - molecular, genes, lipids Flashcards
excess ATP, dATP, decreased lymphocyte count
ADA (adenosine deaminase deficiency), AR mutation
SCID
ADA (adenosine deaminase deficiency), AR mutation
3 mo boy with delayed motor development, develops dystonia. 2 years later exhibits compulsive nail biting and banging head against wall. Develops renal failure and arthritis.
Lesch-Nyhan Syndrome - mutation in HGPRT
excess uric acid + adenine + guanines
Lesch-Nyhan Syndrome - mutation in HGPRT (converts hypoxanthine to IMP and guanine to GMP
HGPRT stands for:
HGPRT: Hyperuricemia Gout Pissed off (aggression, self-mutilation) Retardation (intellectual disability) DysTonia
trmt for excess uric acid + adenine + guanines?
allopurinol or febuxostat (2nd line)
degenerate codon definition
most a.a. are encoded by multiple codons
unambiguous codon definition
each codon specifies 1 a.a.
commaless codon definition
read from a fixed starting point as a continuous sequence of bases
universal codon definition (exception to this?)
genetic code is conserved throughout evolution
exception in humans: mitochondria
difference btwn DNA pol I and III
Pol III - 5’->3’ synthesis, proofreads with 3’->5’ exonuclease, LEADING + LAGGING strand
Pol I - same fxn as pol III, but can also excise RNA primer with 5’->3’ exonuclease, LAGGING strand only
Rx that inhibits DNA topoisomerase in prokaryotes
fluoroquinolones
leading strand orientation?
lagging strand orientation?
leading: 3’ –> 5’
lagging: 5’ –> 3’
difference between transition and transversion
Transition - change within the same class
Transversion - change to a different class
Nonsense mutation
Nucleotide substitution resulting in early stop codon.
Missense mutation
Nucleotide substitution resulting in changed amino acid (conservative if new amino acid is similar in chemical structure).
disease with defective nucleotide excision repair
xeroderma pigmentosum, AR
disease with defective mismatch repair
HNPCC
disease with defective non-homologous end joining
ataxia telangiectasia
how is DNA and RNA template read and synthesized during transcription/translation?
DNA: 3 –> 5 (synthesized 5’–>3’)
mRNA: 5 –> 3 (synthesized N–C terminus)
mRNA stop codons?
UGA = U Go Away. UAA = U Are Away. UAG = U Are Gone.
where is the TATA box located?
promoter region
3 types of eukaryotic RNA polymerase
I - rRNA (most numerous; “Rampant”)
II - mRNA (largest, “Massive”)
III - tRNA (smallest, “Tiny”)
types of prokaryotic RNA polymerase
1 RNA polymerase, but makes all 3 (rRNA, mRNA, tRNA)
polyadenylation signal
AAUAA
P bodies
distinct foci in cytoplasm of eukaryotic cell - contains enzymes involved in mRNA turnover:
- decap and degrade unwanted mRNAs
- store mRNA until needed
- repress translation via miRNAs (related to siRNAs)
hnRNA
precursor to mRNA. undergoes processing in the nucleus:
- 5’ cap
- 3’ polyadenylation
- splicing out introns
snRNPs are found in? associated disease?
found in spliceosome (in nucleus, where pre-mRNA is cleaved form mRNA)
associated dz: SLE - contains anti-Smith antibodies against spliceosomal snRNPs
snRNPs are found in? associated disease?
found in spliceosome (in nucleus, where pre-mRNA is cleaved form mRNA)
associated dz: MCTD - contains anti-U1 RNP antibodies against spliceosomal snRNPs
what accounts for the degeneracy of genetic code?
tRNA wobble - accurate base pairing is required only in the first 2 nucleotide positions of an mRNA codon. Codons differing in the 3rd “wobble” position may code for the same tRNA/amino acid
What initiates mRNA translation?
GTP hydrolysis
Eukaryotic ribosomes
40S + 60S –> 80S (Even)
prokaryotic ribosomes
30S + 50S –> 70S (Odd)
what normally inhibits G1-to-S progression?
p53 and hypophosphorylated Rb
Neurons, skeletal and cardiac muscle, RBCs are considered to be what type of cells relative to the cell cycle?
permanent - remain in G0, regenerate from stem cells
Hepatocytes, lymphocytes are considered to be what type of cells relative to the cell cycle?
Stable (quiescent) - enter G1 from G0 when stimulated.
Bone marrow, gut epithelium, skin, hair follicles, germ cells are considered to be what type of cells relative to the cell cycle?
labile - never go to G0, divide rapidly with a short G1. Most affected by chemotherapy.
Nissl bodies?
found in RER in neurons- makes NTs for secretion
RER makes…
most abundant in…
secreted proteins
abundant in goblet cells of small intestines, plasma cells
SER makes…
most abundant in…
steroids and detoxes drugs and poisons
abundant in hepatocytes, adrenal cortex, gonads
residue added to proteins for trafficking to lysosomes
implicated in what disease
mannose-6-phosphate
I-cell disease (inclusion cell disease) - failure of the Golgi to phosphorylate mannose residues
patient with elevated serum proteases, glycosylases, lipases, hydrolases
I-cell disease (inclusion cell disease) - failure of the Golgi to phosphorylate mannose residues
I-cell disease (inclusion cell disease) features
coarse facial features clouded corneas restricted joint movement (claw shaped hands) high plasma levels of lysosomal enzymes Often fatal in childhood
Signal recognition particle (SRP)
cytosolic ribonucleoprotein that traffics proteins from the ribosome –> RER.
Absent or dysfunctional SRP –> proteins accumulate in the cytosol.
COPI
RETROgrade trafficking
Golgi –> Golgi; Golgi –> ER.
COPII
ANTEgrade trafficking
Golgi –> Golgi; ER –> Golgi.
misfolded proteins in the RER are destined for..?
polyubiquinated and targeted by proteasomes
centriole configuration + function
centrioles (9x3)
two pairs form one centrisome
basal body configuration + function
9x3 (+2) nucleation site for growth of axoneme microtubules
centrisome configuration + function
2 centrioles (9x3) serves as anchoring sites for proteins that anchor microtubules
cilia structure
9 + 2 (forms motile cilia; many projections)
9 + 0 (forms motile cilia; forms one projection from cell)
where is 9 + 0 microtubule configuration usually found?
non-motile (1˚ cilia) - serve as a sensory receptor on primitive node cells to establish R/L axis of body
situs inversus
congenital condition in which the major visceral organs are reversed or mirrored from their normal positions - dextrocardia on CXR
due to primary ciliary dyskinesia
situs inversus, chronic sinusitis, and bronchiectasis
Kartagener syndrome - immotile cilia prevents removal of mucus/pathogens from sinuses and respiratory tract
often have ectopic pregnancies or immobile sperm as well
Kartagener syndrome etiology
1° ciliary dyskinesia - immotile cilia due to a dynein arm defect
Drugs that affect microtubules
Microtubules Get Constructed Very Poorly):
- Mebendazole (anti-helminthic)
- Griseofulvin (anti-fungal)
- Colchicine (anti-gout)
- Vincristine/Vinblastine (anti-cancer)
- Paclitaxel (anti-cancer)
Ouabain MoA
binding to K+ site on Na/K ATPase
Cardiac glycosides
digoxin and digitoxin
digoxin and digitoxin MoA
directly inhibit the Na/K ATPase; leads to indirect inhibition of Na+/ Ca2+ exchange –> increase [Ca2+]i –> increase cardiac contractility.
Collagen Type I
associated dz?
Bone, Skin, Tendon, Dentin, Fascia, CORNEA, SCAR TISSUE
Osteogenica Imperfecta
Collagen Type II
cartilage, vitreous body, nucleus pulposus
Collagen Type III
Reticulin - BV, Skin, Uterus, Fetal tissue, GRANULATION tissue
Collagen Type IV
associated dz?
Basement membrane (“four” = “floor”), basal lamina, LENS
Alport Syndrome - defect in synthesis
Goodpasture Syndrome - ab attack
Vimentin stain
Connective tissue
“Men like to connect tissues”
Desmin
muscle (desMin)
GFAP
neuroglia
cytokeratin
epithelial cells
neurofilaments
neurons
proline + lysine should make you think of
preprocollagen
vitamin c is required for what? deficiency results in
hydroxylation of proline+lysine residues on collagen. Deficiency –> scurvy
triple helix of 3 collagen a chains is called this:
where is it formed?
deficiency results in:
pro-collagen, formed in RER
deficiency: osteogensis imperfecta
defect in cross-linking of tropocollagen molecules to form collagen FIBRILS
where does this cross-linking process normally occur? What d/o do you see this in?
extracellular (outside fibroblasts)
Ehler-Danlos
decrease in production of normal type I collagen
sx?
Osteogenica imperfecta; autosomoal dominant
- factures
- blue sclerae
- hearing loss
- dental imperfections
ehlers-danlos syndrome - classical type
type V collagen deficiency; joint + skin sx (hyperextensible skin, hypermobile joints)
ehlers-danlos syndrome - vascular type
type III collagen deficiency: vascular (berry/aortic aneurysms) and organ rupture
patient w/ brittle, kinky hair, growth retardation, and hypotonia
Menkes disease - CT dz caused by impaired Cu absorption and transport (Cu is required for LYSYL OXIDASE to cross-link extracellular tropocollagen into collagen fibrils)
mutation in a glycoprotein that forms a sheath around elastin
Marfan syndrome - defect in fibrillin
deficiency in this enzyme that results in excess elastase activity.
patients should avoid this:
A1AT deficiency (emphysema)
must avoid smoking
what normally inhibits elastase?
mutation results in..?
A1AT
mutation: emphysema
northern blot
RNA
south-western blot
DNA binding proteins (TFs) - using labeled oligonucleotide probes
Indirect elisa
uses a test antigen to see if a specific antibody is present in the patient’s blood
direct elisa
uses a test antibody to see if a specific antigen is present in the patient’s blood
sensitivity/specificity of elisa?
both approaches 100
FISH
fluorescence in situ hybridization - RNA/DNA probe to localize specific genes on chromsomes
type of nuclei acid used in cloning
mRNA
1) Expose mRNA to RT –> cDNA (no introns).
2) Insert cDNA fragments into bacterial plasmids w. antibiotic resistance genes.
3) Transform recombinant plasmid into bacteria.
4) . Surviving bacteria on antibiotic medium produce cDNA
dsRNA
RNAi (complementary to a mRNA sequence of interest; promotes degradation of target mRNA)
karyotyping uses what type of chromosomes?
metaphase chromsoomes
Codominance
example?
Both alleles contribute to the phenotype of the heterozygote.
Blood groups A, B, AB
α1-antitrypsin deficiency
Variable expressivity
example?
Phenotype varies among individuals with same genotype.
2 patients with NF1 may have varying disease severity.
Incomplete penetrance
example?
Not all individuals with a mutant genotype show the mutant phenotype.
BRCA1 mutation does not always result in breast/ovarian cancer
Pleiotropy
example?
One gene => multiple phenotypic effects
Untreated phenylketonuria (PKU) => light skin, intellectual disability, and musty body odor.
Anticipation
example?
Increased severity / earlier onset of disease in succeeding generations.
Trinucleotide repeat diseases (e.g., Huntington disease).
Loss of heterozygosity
example?
If a patient inherits or develops a mutation in a tumor suppressor gene, the complementary allele must be deleted/mutated before cancer develops. This is not true of oncogenes.
Retinoblastoma and the “two-hit hypothesis.”
Dominant negative mutation
heterozygote produces a nonfunctional altered protein that also prevents the normal gene product from functioning.
Linkage disequilibrium
certain alleles at 2 linked loci to occur together more often than expected by chance. Measured in a population
Mosaicism
example?
genetically distinct cell lines in the same individual that arises from mitotic errors after fertilization; can be somatic vs gonadal
McCune-Albright syndrome = lethal if somatic; survivable if mosaic.
somatic mosaicism
gonadal mosaicism
example?
Somatic mosaicism—mutation propagates through multiple tissues or organs.
Gonadal mosaicism—mutation only in egg or sperm cells.
McCune-Albright syndrome = lethal if somatic; survivable if mosaic
Locus heterogeneity
Allelic heterogeneity
locus = mutations at different loci can produce a similar phenotype (Albinism)
Allelic = different mutations in the same locus produce the same phenotype (β-thalassemia)
Heteroplasmy
Presence of both normal and mutated mtDNA, resulting in variable expression in mitochondrial inherited disease.
Uniparental disomy
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent; EUPLOID
compare heterodisomy vs isodisomy
heterodisomy vs isodisomy
Heterodisomy (heterozygous) = meiosis I error.
Isodisomy (homozygous) = meiosis II error or postzygotic chromosomal duplication of one of a pair of chromosomes, and loss of the other of the original pair.
Hardy-Weinberg population genetics eqns
p^2 + 2pq + q^2 = 1 and p + q = 1, which implies that:
p2 = frequency of homozygosity for allele p q2 = frequency of homozygosity for allele q 2pq = frequency of heterozygosity
carrier frequency, if an autosomal recessive disease
2pq (hardy weinberg)
frequency of an X-linked recessive disease in males? females?
males = q and in females = q^2
hyperphagia, obesity, intellectual disability, hypogonadism, and hypotonia.
Prader-Willi syndrome
gene from mom is normally silent and paternal gene is deleted/ mutated
Prader-Willi syndrome
inappropriate laughter (“happy puppet”), seizures, ataxia, and severe intellectual disability.
AngelMan syndrome
gene from dad is normally silent and Maternal gene is deleted/mutated.
AngelMan syndrome
predict inheritance: many generations, both male and female, affected
Autosomal dominant
predict inheritance: 25% of offspring from 2 carrier parents are affected; usually seen in only 1 generation
Autosomal recessive
predict inheritance: sons of heterozygous mothers have a 50% chance of being affected. No male-to-male transmission
X-linked recessive
Transmitted through both parents. Mothers transmit to 50% of daughters and sons; fathers transmit to all daughters but no sons.
X-linked dominant
Transmitted only through the mother. All offspring of affected females may show signs of disease.
Mitochondrial inheritance
chromosome mutation in ADPKD
16 - PKD1, 4 - PKD2 “16 letters in polycystic kidney”
chromosome mutation in FAP
5 - APC gene “5 words in polyp”
mutation in familial hypercholesterolemia
defective or absent LDL receptor; Elevated LDL, severe atherosclerotic disease early in life, and tendon xanthomas (classically in the Achilles tendon)
mutation in Hereditary hemorrhagic telangiectasia
d/o of blood vessels; telangiectasia, recurrent epistaxis, skin discolorations, AVMs, GI bleeding, hematuria.
mutation in Hereditary spherocytosis
spectrin or ankyrin defect; hemolytic anemia; increased MCHC. Treatment: splenectomy.
chromosome mutation in Huntington disease
4 - CAG trinucleotide repeat (anticipation); depression, progressive dementia, choreiform movements, caudate atrophy, and decrease levels of GABA and ACh in the brain.
mutation in Marfan’s
Fibrillin-1 gene; tall with long extremities, pectus excavatum, hypermobile joints, and long, tapering fingers and toes (arachnodactyly); cystic medial necrosis of aorta
mutation in Multiple endocrine neoplasias (MEN)
MEN 2A and 2B are associated with ret gene.
chromosome mutation in NF1
17 - autosomal dominant; 100% penetrance with variable expression; café-au-lait spots and cutaneous neurofibromas.
chromosome mutation in NF2
22 - bilateral acoustic schwannomas, juvenile cataracts, meningiomas, and ependymomas
chromosome mutation in tuberous sclerosis
numerous benign hamartomas; incomplete penetrance, variable expression
chromosome mutation in von Hippel-Lindau disease
3 - VHL gene; development of numerous tumors
chromosome mutation in Cystic fibrosis
chromosome 7 - ATP-gated Cl- channel; mutation causes proteins to be retained in the RER (not transported to the cell membrane)
= secretes Cl− in lungs and GI tract
= reabsorbs Cl− in sweat glands
Cystic fibrosis pathophysiology and diagnosis
= secretes Cl− in lungs and GI tract
= reabsorbs Cl− in sweat glands
dx: increase Cl- in sweat, contraction alkalosis and hypokalemia because of ECF H2O/Na+ losses and concomitant renal K+/H+ wasting
Cystic fibrosis treatment
N-acetylcysteine = loosen mucus plugs (cleaves disulfide bonds within mucus glycoproteins)
Dornase alfa (DNAse) to clear leukocytic debris (mucolytic)
Cystic fibrosis complications
- Recurrent pulmonary infections (e.g., Pseudomonas)
- chronic bronchitis and bronchiectasis
- Reticulonodular pattern on CXR
- pancreatic insufficiency, malabsorption and steatorrhea
- nasal polyps
- meconium ileus in newborns
- Infertility in males (absence of vas deferens, absent sperm)
- Fat-soluble vitamin deficiencies (A, D, E, K)
chromosome mutation in Duchenne’s
X-linked frameshift mutation (dystrophin gene (DMD) has the longest coding
region of any human gene -> increases chance of spontaneous mutations)
lab diagnosis of Duchenne’s
increase CPK and aldolase
WB and muscle biopsy to confirm
Symptoms of Duchenne’s
- weakness begins in pelvic girdle muscles and progresses superiorly
- Pseudohypertrophy of calf muscles
- Gower maneuver—patients use upper extremity to help them stand up
- Onset before 5 years of age
- Dilated cardiomyopathy is common cause of death.
Becker’s
X-linked point mutation in dystrophin gene (no frameshift as in Duchenne’s)
post- pubertal macroorchidism (enlarged testes), long face with a large jaw, large everted ears, autism, mitral valve prolapse.
Fragile X syndrome (trinucleotide repeat d/o)
X-linked affecting methylation patterns of FMR1 gene
(2nd most common cause of intellectual disability)
chromsome mutation in Down syndrome
21
chromsome mutation in Edward syndrome
18
chromsome mutation in Patau syndrome
13
increased nuchal translucency and hypoplastic nasal nasal bone
decreased serum PAPPA, increased ßhCG
1st trimester Down Syndrome
low AFP, estriol
increase hCG, inhibin
2nd trimester Down Syndrome
increased nuchal translucency and hypoplastic nasal nasal bone
decreased serum PAPPA, ßhCG
Edwards Syndrome (18) - first trimester
low AFP, estriol, hCG, inhibin
Edwards Syndrome (18) - second trimester
low β-hCG, PAPP-A
increased nuchal translucency
Patau Syndrome (13)
evere intellectual disability, rocker- bottom feet, micrognathia (small jaw), low-set Ears, clenched hands, prominent occiput, congenital heart disease.
Death usually occurs within 1 year of birth.
Edwards syndrome (trisomy 18),
Severe intellectual disability, rocker- bottom feet, microphthalmia, microcephaly, cleft liP/Palate, holoProsencephaly, Polydactyly, congenital heart disease.
Death usually occurs within 1 year of birth.
Patau syndrome (trisomy 13)
intellectual disability, flat facies, prominent epicanthal folds, single palmar crease, gap between 1st 2 toes, duodenal atresia, Hirschsprung disease, congenital heart disease (most commonly ostium primum-type atrial septal defect [ASD]), Brushfield spots.
Down Syndrome (21)
Associated with increase risk of ALL, AML, and Alzheimer disease (> 35 years old).
Down Syndrome
these numbers make you think of…?
13, 14, 15, 21, and 22
Robertsonian translocation - these are acrocentric chromosomes (chromosomes with centromeres near their ends)
balanced translocations = no abnormal phenotype
Unbalanced translocations = miscarriage, stillbirth, and chromosomal imbalance (e.g., Down syndrome, Patau syndrome).
microcephaly, moderate to
severe intellectual disability, high-pitched crying/mewing, epicanthal folds, cardiac abnormalities (VSD)
Cri du chat = cry of the cat
chromsome abnormality in Cri-du-chat syndrome
5 - microdeletion of short arm
Cri du chat syndrome
“elfin” facies, intellectual disability, hypercalcemia (increased sensitivity to vitamin D), well-developed verbal skills, extreme friendliness with strangers, cardiovascular problems.
7 - microdeletion of long arm (deleted region includes elastin gene)
Williams syndrome
22q11 deletion
DiGeorge Syndrome - thymic, parathyroid, and cardiac defects. "CATCH-22" Cleft palate Abnormal facies Thymic aplasia -> T-cell deficiency Cardiac defects Hypocalcemia 2° to parathyroid aplasia
thymus develops from which branchial pouches?
Due to aberrant development of 3rd and 4th branchial pouches
main processes that go on after a fasting state?
Hepatic glycogenolysis (major)
hepatic gluconeogenesis, adipose release of FFA (minor).
Glucagon, adrenaline stimulate use of fuel reserves.
main processes that go on during d1-3 of starvation?
Blood glucose maintained by:
hepatic glycogenolysis + gluconeogenesis
adipose release of FFA
muscle + liver shift fuel use from glucose -> FFA
Hepatic gluconeogenesis relies on these things
peripheral tissue: lactate + alanine
adipose tissue: glycerol and propionyl- CoA (from odd-chain FFA—the only TG components that contribute to gluconeogenesis)
main processes that go on after d3 of starvation?
Adipose stores (ketone bodies become the main source of energy for the brain)
After these are depleted, vital protein degradation accelerates, leading to organ failure and death.
Rate-limiting step of cholesterol synthesis?
HMG-CoA
Statins competitively and reversibly inhibit HMG-CoA reductase.
Pancreatic lipase
degradation of dietary triglycerides (TG) in small intestine.
Lipoprotein lipase (LPL)
degradation of TG circulating in chylomicrons and VLDLs. Found on vascular endothelial surface.
Hepatic TG lipase (HL)
degradation of TG remaining in IDL.
Hormone-sensitive lipase
degradation of TG stored in adipocytes.
LCAT
catalyzes esterification of cholesterol.
Cholesterol ester transfer protein (CETP)
mediates transfer of cholesterol esters to other
lipoprotein particles.
ApoE
Mediates chyloµ remnant uptake by LDL receptors on hepatocytes (liver uptake)
ApoAI
Activates LCAT to esterify cholesterol on nascent HDL -> forms mature HDL
ApoCII
activates Lipoprotein Lipase on peripheral cells to deliver TGs
ApoB48
liver sends this out during the FED state to mediate chylo-µ transport from the gut into circulation (delivers dietary TG to peripheral tissues)
ApoB100
packaged into VLDL particles that the liver sends out during the FASTING state to deliver cholesterol + FA to peripheral tissues
chylomicron function? produced by?
1) delivers dietary TGs to peripheral tissue.
2) delivers cholesterol to liver in the form of chylomicron remnants, which are mostly depleted of their TGs.
3) Secreted by intestinal epithelial cells, packaged w/ ApoB48, ApoE, ApoCII and ApoCIII
VLDL function? produced by?
packaged with ApoB100; delivers HEPATIC TGs to peripheral tissues during FASTING state
IDL function? produced by?
Formed in the degradation of VLDL; delivers remaining TGs and cholesterol to liver.
LDL function? produced by?
Delivers hepatic cholesterol to peripheral tissues. Formed by hepatic lipase modification of IDL in the peripheral tissue. Taken up by target cells via receptor-mediated endocytosis.
HDL function? produced by?
Mediates reverse cholesterol transport from periphery to liver. Acts as a repository for ApoC and ApoE (which are needed for chylomicron and VLDL metabolism). Secreted from both liver and intestine. Alcohol increases synthesis.
Type I hyper-chylomicronemia
- pathophys?
- increased blood levels of?
ø Lipoprotein lipase or altered Apo C-II (AR)
forms excess Chylomicrons, TG, cholesterol
Type IIa—familial hyper- cholesterolemia
- pathophys?
- increased blood levels of?
ø LDL receptors (AD)
forms excess LDL, cholesterol
IV—hyper- triglyceridemia
- pathophys?
- increased blood levels of?
Hepatic overproduction of VLDL (AD)
forms excess VLDL, TG
familial dyslipidemia that causes
- pancreatitis
- hepatosplenomegaly
- eruptive/pruritic xanthomas
Type I hyperchylomicronemia (no risk for atherosclerosis)
familial dyslipidemia that causes
- accelerated atherosclerosis (may have MI before 20)
- tendon xanthomas
- corneal arcus
Type IIa—familial hyper- cholesterolemia - LDL increases atheroma risk
familial dyslipidemia that causes pancreatitis only
Type IV hyper- triglyceridemia
Telomerase
RNA dependent DNA polymerase (in other words, reverse transcriptase) that adds DNA to 3’ end of chromosomes to avoid loss of genetic material w/ every dupliation
what is common to ALL tRNAs (both eukaryotic and prokaryotic)?
CCA at 3’ end of tRNA; serves as a linker of the tRNA and the a.a.
difference btwn T arm and D arm of tRNA
T arm = contains sequence for tRNA ribosome binding
D arm = contains dihydrouracil for tRNA recognition by the correct aminoacyl tRNA synthesis
linker of a.a. and the proper tRNA
aminoacyl-tRNA synthetase (1 per a.a.; serves as a matchmaker) - serves as a match maker and is responsible for adding the right a.a. to the right tRNA.
tough job.
collagen is comprised mostly of
glycine (followed by proline + lysine)
how does Arsenic affect glycolysis?
physical presentation of this?
causes it to produce 0 net ATP because it inhibits lipoic acid, which is present in the pyruvate dehydrogenase complex as well as the a-ketoglutarate dehydrogenase complex
physical presentation: vomiting, rice water stool, and GARLIC breath…say what?
gene mutation associated with Maturity-onset diabetes of the young (MODY)
Glucokinase
essential a.a.?
methionine Valine histidine Isoleucine Phenylalanine Threonine Tryptophan Leucine Lysine
PITT Essentially LIEd to LUCy about going to the MET with HIS ex VALerie
dyslipidemias - which two particles are responsible for causing pancreatitis?
chyloµ + VLDL
dyslipidemias - which two particles are responsible for causing fatty liver?
VLDL + IDL
dyslipidemias - which two particles are responsible for causing pancreatitis?
LDL + lipo(a)
what happens if hepatic lipase is mutated?
increased HDL - good mutation to have!
what happens if ABCA1 is mutated?
ABCA1 functions to remove excess cholesterol + FFA from peripheral tissues
∆ ABCA1 = Tangier’s disease - severe reduction in HDL particles and accumulation of cholesterol in many body tissues
Presentation:
- Tangier’s tonsils (extremely enlarged, orange/yellow)
- premature atherosclerosis
- slightly elevated amounts of fat in circulation
- other signs
- > enlarged spleen, liver
- > clouding of cornea
- > early onset of cardiovascular disease
