Biochem / Immuno Review Flashcards
Heterochromatin
methylation vs acetylation
Increased methylation
Decreased acetylation
DNA methylation
Template strand cytosine and adenine are methylated in DNA replication which allows mismatch repair enzymes to distinguish between old and new strands in prokaryotes
What relaxes DNA coiling allowing for transcription
Histone acetylation
Deamination of cytosine makes
Deamination of adenine makes
Methylation of uracil makes
Deamination of cytosine makes Uracil
Deamination of adenine makes Guanine
Methylation of uracil makes thyamine
Amino acids necessary for purine synthesis
GAG
Glycine
Aspartate
Glutamine
Inhibit dihydrofolate reductase
in what pathway
Methotrexate (MTX)
Trimethoprim (TMP)
Pyrimethamine
Pyrimidine synthesis
Thymidylate synthase inhibited by
what pathway
5-fluorouracil
pyrimidine synthesis
Inhibits purine synthesis pathway
6- mercaptopurine ‘
- azathioprine is prodrug
- inhibits PRPP aminotransferase
Mycophenolate
Ribavirin
- inhibit inosine monophosphate dehydrogenase
Inhibits ribonucleotide reductase
Hydroxyurea
Allopurinol MOA
Other drug with same MOA
inhibits xanthine oxidase
Febuxostat
One of the major causes of SCID
AR
adenosine deaminase deficiency cant degrade deoxyadenosine ( dATP)
Self mutilation
Intellectual disability
Lesch-Nyhan syndrome
- X linked
Defective purine salvage
HGPRT absent
HGPRT
- Hyperuricemia
- Gout
- Pissed off
- Retardation
- Dystonia
Lesch-Nyhan syndrome see an increase in
Phosphoribosyl pyrophospahte amidotransferase (PRPP aminotransferase)
What two amino acids are coded for by only 1 codon
methionine (AUG)
Tryptophan (UGG)
Inhibits eukaryotic topoisomerase I
Irinotecan
Topotecan
Inhibits eukaryotic topoisomerase II
Etoposide
teniposide
Fluroquinolones
Inhibit prokaryotic topoisomerase II and topoisomerase IV
Topoisomerase II aka as
Topoisomerase II= DNA gyrase
Fluroquinolones
Telomerase
- prokaryotes or eukaryote
- MOA
- pattern
Eukaryotes only
RNA-dependent DNA polymerase that adds DNA to 3’ ends of chromosome to avoid loss of genetic material with every duplication
TTAGGG repeat
Transition vs transversion in mutations
Transition
- purine to purine
- pyrimidine to pyriminde
Transversion
- purine to pyrimidine or reverse
Example of missense mutation disease
Sickle cell disease
Glutamic acid –> valine
Stop codons
UAG
UAA
UGA
Examples of frameshift mutation disease
Duchene muscular dystrophy
Tay-Sachs
Splice site mutation
Mutation at a splice site –> retained intron in mRNA –> protein impaired or altered function
Dementia
Epilepsy
Some types of beta thalassemia
Lac operon
- low glucose does what
increases activity of adenylate cyclase –> cAMP from ATP and activation of CAP
Origins of replication for DNA vs RNA
Eukaryote
- linear
- multiple origins of replication
Prokaryote
- Circular
- Single origin of replication
Defective nucleotide excision repair leads to what diease
xeroderma pigmentosum
Prevents repair of pyrimidine dimers
Base excision repair begins with
Glycosylase removes an altered base and creates AP site (apurinic/ apyrimidinic)
Mismatch repair occurs during what phase of cell cycle
defective in
S phase
Defective in lynch syndrome (hereditary nonpolyposis colorectal cancer)
Nonhomologous end joining is defective in
Ataxia telangiectasia (AR)
- ataxia
- spider angiomas
- IgA deficiency
Breast/ovarian cancers with BRCA1 mutation
Fanconi anemia
- aplastic anemia
- Short stature
- cafe-au lait spots
- thumb/ radial defects
- reabsorption defect in PCT (increased excretion of everything)
Promoter site
- what binds
- sequence
RNA polymerase II binds
TATA
CAAT
Actinomycin D
inhibits RNA polymerase in both prokaryotes and eukaryotes
Inhibits DNA-dependent RNA polymerase in prokaryotes
Rifampin
mRNA quality control occurs where
at cytoplasmic processing bodies (p-bodies) which contain exonucleases, decapping enzymes and microRNA
Anti-smith Ab are antibodies to
SLE
Antibodies to spliceosomal snRNPs
Part called that is removed with spliceosome
Lariat
Part of DNA removed
Introns
Introns stay IN the nucleus
Posttranscriptionally regulate gene expression of mRNA by targeting 3’ untranslated region for degradation or translational repression
microRNA
Component of ribosome that catalyzes peptide bond formation during translation
rRNA
tRNA structure
Acceptor stem= ACC
T arm= binds tRNA to ribosome
Anticodon loop
- no functional role
D arm
- dihydrouridine residues
- how aminoacy-tRNA synthetase recoginzes tRNA
tRNA binds to mRNA in which way
Antiparallel fashion
Initiation
Elongation
Termination
of protein synthesis powered by
GTP
ATP- tRNA activation
GTP- tRNA (going places, translocation)
Tumor suppressor pathway
p53 induces p21 which inhibits CDKs –>
hypophosphorylation (activation) of Rb –>
inhibition of G1-S progression
Permanent cell types
Stable cell types
Labile cell types
Permanent cell types
- Remain in Go
- regenerate from stem cells
- neurons, skeletal and cardiac muscle, RBcs
Stable cell types
- Enter G1 from G0 when stimulated
- Hepatocyets
- Lymphocytes
Labile cell types
- Never go to G0
- Divide rapidly with a short G1
- Most affected in chemo
- Bone marrow, gut epithelium, skin, hair follicles, germ cells
Peptides formed where
Steroids formed where
NE, GABA, ACh, Dopamine, Epinephrine, serotonin
- formed in rough ER
Steroids= smooth ER
What all occurs in mitochondria
TCA cycle
Fatty acid oxidation
Electron transport chain
Oxidation of long and branched chain fatty acids
also oxidation of?
Peroxisomes
- via beta oxidation
also amino acids and ethaol
Hydrogen peroxide degradation occurs where
Peroxisomes
Degradation of ubiquitinated proteins occurs where
Proteasomes
Coarse facial features
Clouded corneas
Restricted joint movements
High plasma level of lysosomal enzymes
Fatal childhood
- names
- defect
- failure
- what happens
I-cell disease
(inclusion cell disease, mucolipidosis type II)
Inherited lysosomal storage disorder
defect in N-acetylglucosaminyl-1-phosphotransferase
failure of golgi to phosphorylate mannose residues on glycoproteins (decrease mannose-6-phosphate)
Proteins secreted extracellularily rather than to lysosomes
Vesicular trafficking proteins
COPI:
- golgi –> golgi
- golgi –> ER
- backwards (retrograde)
COPII
- ER –> golgi
- forward (anterograde)
Clathrin
- golgi –> lysosomes
Two (COPII) steps forward (anterograde); one step (COPI) step back (retrograde)
Disease of peroxisome
Zellweger syndrome
- hypotonia
- seizures
- hepatomegaly
- early death
Refsum
- scaly skin
- ataxia
- cataracts/ night blindness
- shortening 4th toe
- epiphyseal dysplasia
Microfilament
Intermediate filament
Microfilament
- actin, microvilli
Intermediate
- desmin, cytokeratin, lamins, neurofilaments
Vimentin
Desmin
GFAP
Vimentin
- mesenchymal tissues (fibroblast, endothelial cells, macrophages)
- sarcoma, meingioma
Desmin
- muscle
- rhabdomyosarcoma
GFAP
- NeuroGlia
- (astrocytes, schwann cells, olidodendrocytes)
- Astrocytoma, glioblastoma
Transport along microtubule
Dynein
- retrograde to microtubule (+ –> - )
Kinesin
- anterograde to microtubules ( - –> +)
Negative near nucleus
Positive end Points to periphery
Kin (Keen) to go out (anterograde)
Dying to come back home (retrograde)
Drugs that act on microtubules
Microtubules Get Constructed Very Poorly
Mebendazole (antihelminthic) Griseofulvin (antifungal) Colchicine (antigout) Vincristine/Vinblastine (anticancer) Paclitaxel (anticancer)
Proteins help form the fibrillar network that lines the inside of the nuclear envelope
Regulate gene transcription
Lamins
Secures organelles inside the cytosol and provides resistance to mechanical stress
Vimentin
Primary ciliary dyskinesia
Kartagener syndrome
Immotile cilia due to dynein arm defect
Recurrent pulmonary infection Digital clubbing Abnormal immotile spermatoozoa Sinus inversus dysfunctional fallopian tube cilia
Bronchiectasis
Recurrent sinusitis
Chronic ear infections
Increased risk of ectopic pregnancy
Conductive hearing loss
Cilia structure
9 pairs of 2 microtubes are in a circle
Basal body: 9 microtubule triplets
Na/K pump
3 Na out of cytosol –> Extracellu
2 K in to cytosol
ATP on cytosolic side
Pumpkin= pump K in
Digoxin MOA
directly inhibits Na/K ATPase which leads to indirect inhibition of Na/Ca exchange
Increase Ca concentration
Increase cardiac contractility
Collagen types
Type I: Bone
Type II: cartilage
carTWOlage
Type III: vascular
(ehlers-danlos)
ThreE D
Type IV: basement membrane
- Alport
- Good pasture
Collagen made up
Gly- Proline- lysine
Vit C in collagen formation
hydroxylation of proline and lysine requires Vit C
Osteogeneis imperfecta collagen defect
Cant form triple helix of collagen
Glycosylation step
Ehlers Danlos collagen problem occurs which step
Proteolytic processing
Problem with cleavage of disulfide-rich terminal region of pro-collagen –> insoluble tropocollagen
Cross linking
Osteogenesis imperfecta
- gene defect
- inheritence
- collagen involved
- symptoms (3)
COL1A1 and COL1A2
AD
Type I collagen
Multiple fractures
Blue sclerae
Hearing loss
Hyperextensible skin
Hypermobile joints
- assoc with
- mutation
- collagen
Ehlers-Danlos
Berry and aortic aneurysms
Classic type
- Type V collagen
- COL5A1, COL5A2
Vascular type
- deficent type III collagen
Brittle kinky hair
Growth retardation
Hypotonia
Menkes disease
X linked
Impaired copper absorption
defect ATP7A
decreased activity of lysyl oxidase
Elastin rich in
Proline
Glycine
Lysine
Elastin broken down by
inhibited by
Elastase
Elastase inhibited by alpha 1 antitrypsin
Defect in COL1A1 and COL1A2
Osteogenesis imperfecta
Tall with long limbs
Hypermobile joints
Long fingers and toes
subluxation of lens upward
- inheritence
- mutation
- associated with
Marfan syndrome
AD
FBN1 gene chr 15
Defective fibrillin
- glycoprotein forms sheath around elastin
Cystic medial necrosis of aorta, Aortic incompetence
Disssecting aorta
Floppy mitral valve
What do you need for polymerase chain reaction (PCR)
Dont need exact nucleotide sequence
Need flanking region known to make primer
What do you need for gel electrophoresis
Need restriction sites
Types of blots
SNoW DRoP
Southern: DNA
Northern: RNA
Wester: protein
Used for fetal RBCs in mother’s blood and immunodeficiencies, CD4 count in HIV
Flow cytometry
Used for in genotyping, genetic testing, cancer mutation
Microarrays
What is used in reverse transcriptase PCR
cDNA (lacks introns)
Patients with the same genotype have varying phenotypes
Variable expressivity
Not all individuals with a mutant genotype show the mutant phenotype
Incomplete penetrance
One gene contributes to multiple phenotypic effects
Pleiotrophy
Loss of heterozygosity
If a patient inherits or develops a mutation in a tumor suppressor gene, the complementary allele must be deleted/ mutated before cancer develops
Mutation in mitochondrial DNA
Heteroplasmy
Mutations at different loci cause same phenotype
Locus heterogeneity
More than 1 genetic make up of cells occurring in same individual
Mosaicism
A 39-year-old woman gives birth to a term infant with
an umbilical hernia, Brushfield spots on the iris, macroglossia,
low-set ears, oblique palpebral fissures, and a heart murmur.
The infant survives to childhood and exhibits only mild mental
retardation. Which of the following chromosomal abnormalities,
affecting autosomes, is most likely to be present in
the somatic cells of this child?
A Haploidy
B Monosomy
C Mosaicism
D Tetraploidy
E Triploidy
C. Mosaicism
Unilateral cafe-au-lait spots
Fibrous replacement in bone on one side
Precocious puberty (puberty at 2 y.o)
Enlarge thyroid
McCune Albright syndrome
Mosaicism
Mutation of G-protein signaling
Different mutations in the same locus produce same phenotype
Allelic heterogeneity
Beta-thalassemia
Offspring receives 2 copies of chromosome from 1 parent and no copies from other parent
Uniparental disomy
Hardy-weinberg population genetics
Frequency of X linked recessive disease
- in males=
- in females=
Males= q Females= q ^2
Eats everything
Obese
Intellectual disability
Hypotonia
Other key symptom
Prader-Willi
Maternal imprinting
- Mom gene= silent
- Dad gene= mutated
Hypogonadisum
Inappropriate laughter
Intellectual disability
Other key symptom
AngelMan syndrome
Paternal imprint
- Dad gene= silent
- Mom= mutated
Seizues
Ataxis
X linked dominant disorder
Fragile X
Hypophosphatemic rickets
- Vit D resistant rickets
Alport syndrome
Mitochondrial inheritance what is seen in progeny
All offspring of affected females show signs of disease
Muscle weakness
Lactic acidosis
CNS disease
Muscle biopsy
- Ragged red fibers
- failure of
- biopsy due to
Mitochondrial myopathies
secondary to failure in oxidative phosphorylation
Ragged red fibers due to accumulation of disease mitochondria
Autosomal dominant disease
Von, Von, ALS, Rb, MEN Tubes and sphere and huntington Marfan, Ehlers Dans NF1 and 2, dont FAP too much Autosominal dominant yes this song is clutch Osler, Weber, rondu, achondroplaia Family hypercholestrolemia AD poly kidney disease
Autosomal recessive disease
Alpha, Beta, Pee-ew
Iron, copper, Bern-sou
Hartnup, Glanzman, fanconi
AR yes its true
Cystic fibrosis, pompe-ew
Spingo, muco, sickle-ew
Cori, mcardle, albinism
Von gierke is too
X linked recessive
The itsys bitter hunter’s name was Lesch Fabry
He shot the menike, WASP, and G6P
Up came the Bruton, what a douchy guy
A and B are X linked, dont forget DI
Cystic fibrosis
- gene and chromosome
- affects
- mutation causes
- decrease in
- overall effect
- Labs
CFTR on chr 7
encodes for ATP gated Cl- channel
Misfolded protein retained in RER
Decrease Cl and H20 secretion
Increase Na reabsorption
Abnormally thick mucus secreted into lungs and GI tract
- cilia normal
Alkalosis
Hypokalemia
Cystic fibrosis infections
early infancy: s. aureus
adolescence: pseudomonas
Cystic fibrosis presentation
Absence vas deferens Bronchitis adn bronchiectasis - reticulonodular parttern on CXR - opacification of sinuses - Nasal polyps - clubbing of nails
Weakness in pelvic girdle muscles
Progresses superiorly
- death due to
- labs
Duchenne
Death= cardiomyopathy
Increased CK and aldolase
Becker muscular dystrophy
X linked disorder
Non-frameshift deletion
Muscle weakness
Cataracts
Early balding in men
Gonadal atrophy
Myotonic type I
AD
CTG trinucleotide repeat in DMPK gene –> abnormal expression of myotonin protein kinase
Large Jaw
Macroorchidism
Long face
Large ears
- inheritence
- mutation
- causes
- assoc with
Fragile X syndrome
X linked dominant
Trinucleotide repeat in FMR1 (CGG)
–> hypermethylation
Autism
Mitral valve prolapse
Trinucleotide repeat expansion diseases
Try HUNTing for MY FRAGile Fried eggs
Huntington
Myotonic type I
Fragile X
Friedreich ataxia
Labs Down syndrome
Decreased alpha-fetoprotein
Increased beta hCG
Decreased estriol
Increased inhibin A
CTG
CGG
CAG
GAA
CTG= Myotonic type I
- Cataracts, Toupee, Gonadal atrophy
CGG= Fragile X syndrome
- Chin, Giant Gonads
CAG= Huntington
- Caudate has decreased Ach and Gaba
GAA= friedreich ataxia
- Ataxia GAAit
Edwards syndrome trisomy 18
- signs
- labs
Rocker bottom feet
Overlapping fingers
Low set Ears
Micrognathia
Decreased
- alpha feto protein
- hCG
- estriol
- inhibin (normal)
Patau syndrome trisomy 13
- signs
- labs
Rocker bottom feet Microcephaly cleft lip/palate holoprosencephaly polydactyly
decreased beta hCG
Decreased PAPP-A
Genetic disorder by chromosome
3
- VHL
- renal cell carcinoma
4
- ADPKD (PKD2)
- achondroplasia
- huntington
5
- cri-du-chat
- familial adenomatous polyposis
6
- hemochromatosis
7
- Williams syndrome
- cystic fibrosis
9
- Freidreich ataxis
11
- Wilms
- sickle cell
- beta thalassemia
- MEN1
13
- Patau
- Wilson
- Rb1
- BRCA2
15
- Prader-willi
- Angelmann
- Marfan
16
- ADPKD (PKD1)
- alpha thalassemia
17
- NF1
- BRCA1
- p53
18
- edwards
21
- downs
22
- NF2
- Digeorge
X
- Fragile X
- X linked agammaglobulinemia
- klinefelter
Chromsome 3
- VHL
- renal cell carcinoma
Chromosome 4
4
- ADPKD (PKD2)
- achondroplasia
- huntington
Chromosome 5
5
- cri-du-chat
- familial adenomatous polyposis
Chromosome 6
6
- hemochromatosis
Chromosome 7
7
- Williams syndrome
- cystic fibrosis
Chromosome 9
9
- Freidreich ataxis
Chromosome 11
11
- Wilms
- sickle cell
- beta thalassemia
- MEN1
Chromosome 13
13
- Patau
- Wilson
- Rb1
- BRCA2
Chromosome 15
15
- Prader-willi
- Angelmann
- Marfan
16
- ADPKD (PKD1)
- alpha thalassemia
17
- NF1
- BRCA1
- p53
18
- edwards
21
- downs
22
- NF2
- Digeorge
X
- Fragile X
- X linked agammaglobulinemia
- klinefelte
Chromosome 16
16
- ADPKD (PKD1)
- alpha thalassemia
Chromosome 17
17
- NF1
- BRCA1
- p53
Chromosome 22
22
- NF2
- Digeorge
X chromosome diseases
X
- Fragile X
- X linked agammaglobulinemia
- klinefelter
Cri-du-chat
Microdeletion of short arm of chromosome 5
Microcephaly
High pitched crying/ meowing
epicanthal folds
VSD
Elfin facies Intellectual disability Hypercalcemia Extremely friendly cardiovascular problems
Williams syndrome
Microdeletion of long arm on chr 7
elastin gene
Increased sensitivity to Vit D
B1 B2 (produce) B3 (produce) B5 (produce) B6 B7 B9 B12 C
B1= thiamine
B2= riboflavin
-FAD, FMN
B3= Niacin
- NAD
B5= Pantothenic acid
-CoA
B6= pyridoxine
B7= biotin
B9= Folate
B12= cobalamin
Night blindness
Dry scaly skin
Bitot spots
Vit A def
Vit B1 uses
think ATP
alpha ketoglutarate dehydrogenase
Transketolase
Pyruvate dehydrogenase
Ber1 Ber1
Dry Beri Beri
polyneuritis
Symmetrical muscle wasting
Wet Beri Beri
High out cardiac failure
dilated cardiomyopathy
edema
Fissures at corners of mouth
Vit B2 (riboflavin)
Vit B3 derived from
Niacin
Derived from tryptophan
Hartnup
- inheritence
- deficency
- causes
AR
deficency of tryptophan
no niacin
Hyperpigmentation of sun exposed limbs
Disorientation
Diarrhea
Pellagra can be caused by
Hartnup
Malignant carcioid syndrome
( increased tryptophan metabolism)
Isoniazid (decreased Vit B6)
Alopecia deficiency in
Vit B5 pantothenic acid
part of CoA
Needed for synthesis of neurotransmitters
Vit B6 (pyridoxine)
Vit B9 deficiency causes
Phenytoin
Sulfonamides
Methotrexate
Delayed wound healing Decreased adult hair Loss of taste Loss of smell Rash around mouth and anus
Zinc deficiency
Inhibits alcohol dehydrogenase
Fomepizole
Limiting agent in ethanol metabolism
NAD+
Hydroxylase does
Adds hydroxyl group (-OH)
Carboxylase does
Transfers CO2 gorup w/ help of biotin
Pyruvate dehydrogenase complex makes
Acetyl-CoA + CO2 + NADH
What forms succinyl CoA
Succinyl CoA form
Methylmalonyl-CoA –> methylmalonyl-CoA mutase + B12
Without B12
Increase methylamlonyl CoA
Succinyl CoA –> +B6 –> Heme
FBPase 2 vs PFK2
- fasting state
Fasting
- increase glucagon
- increase cAMP
- increase protein kinase A
- Increase FBPase
More gluconeogenesis
Garlic breath
Rice water stools
Vomiting
QT prolongation
- inhibits
- tx
Arsenic
Inhibits lipoic acid
Inhibits pyruvate dehydrogenase
No acetyl CoA or NADH
Dimercaprol
Pyruvate dehydrogenase complex deficiency
Build up pyruvate –> lactate and alanine
Alanine –> neurlogical defects
Lactic acidosis
X linked
Only major step in tca cycle that doesnt require NAD
Oxaloacetate –> citrate
citrate synthesis
Inhibits part of electron transport chain
Complex I= rotenone
Complex III= antimycin A
Complex IV= cyanide, CO
Complex V= oligomycin
ATP synthase inhibitor
Oligomycin
Inhibits complex V
Uncoupling agents
2,4 Dinitrophenol
Aspirin
Thermogenin in brown fat
Gluconeogenesis irrevesible enzmes
- locations
- requires
Pathway Produces Fresh Glucose
Pyruvate carboxylase
- mitochondria
- biotin, ATP
- activated Acetyl-CoA
Phospheoenolpyruvate carboxykinase
- Cytosol
- GTP
Fructose-1,6-bisphosphatase
- Cytosol
Glucose-6-phosphatase
- ER
Sites of HMP shunt (pentose phosphate pathway)
Lactating mammary glands
liver
Adrenal cortex
RBCs
Asymptomatic
Fructose in blood and urine
Essential fructosuria
Defect in fructokinase
Negative urine dipstick Hypoglycemia Jaundice Cirrhosis Vomiting
Fructose intolerance
Deficiency aldolase B
AR
Fructose-1-phosphate accumulates
Decrease availability of phosphate
- -> inhibit glycogenolysis
- -> inhibit gluconeogenesis
Consumption fruit, juice or honey
FAB GUT
- Fructose is to aldolase as galactose is to Uridyl Transferase
Galactokinase deficiency
AR
Deficency galactokinase
Galactosemia
Infantile cataracts
Child just began feeding Failure to thrive Jaundice Hepatomegaly Infantile cataracts
- deficiency
- inheritence
- accumulation
- serious defects due to
Classic galactosemia
Absence of galactose-1-phosphate uridyltransferase (GALT)
AR
Accumulation of galactitol
Serious defects lead to phosphate depletion
FAB GUT
- Fructose is to aldolase as galactose is to Uridyl Transferase
Diabetes and cataracts
Increased glucose –> glycation of lens protein
Hyperglycemia –> increased formation of sorbitol faster than metabolized to fructose
Sorbitol increase osmotic pressure
- osmotic cellular injury
Enzyme for glucose to sorbitol
Sorbitol to fructose
Aldose reductase
Sorbitol dehydrogenase
Essential amino acids
Private (PVT) TIM HaLL
Phenylalanine Valine (VAL) Threonine Tryptophan Isoleucine Methionine (MET) Histidine (HIS) Leucine Lysine
Basic amino acids
Histidine
Lysine
Arginine
Urea cycle produces
pyruvate
acetyl CoA
Tremor (asterixis) Slurring speech Somnolence Vomiting Cerebral edema Blurring vision
Tx
Hyperammonemia
Tx
Rifaximin
Progressive development of spastic diplegia (paralysis of parts of body on both sides)
Abnormal movements
Growth delay
Arginase deficiency
Elevated levels arginine
Urea and ornithine not produced
No hyperammonemia