FA Biochem

Section

Question	Answer
AAs required for purine synthesis	Glycine, Aspartate, Glutamine
Nucleotide base with ketone	Guanine
Nucleotide base with methyl	Thymine
Hydroxyurea	inhibits ribonucleotide reductase
6-mercaptopurine	inhibits purine synthesis
5-fluorouracil	inhibits thymidylate synthase
Methotrexate	inhibits DHFR
Trimethoprim	inhibits BACTERIAL DHFR
Orotic aciduria	AUTOSOMAL RECESSIVE: Can't covert orotic acid to UMP due to defect in 1) Orotic acid phosphoribosyltransferase, 2) orotidine-5'-phosphate decarboxylase.
SCID	Adenosine deaminase deficiency, leading to increased ATP and dATP, which has negative feedback on DNA synthesis via inhibition of ribinucleotide reductase
Lesch-Nyhan syndrome	X-LINKED RECESSIVE: HGPRT absent. Can't convert hypoxanthine to IMP, guanine to GMP. PURINE RECOVERY PROBLEMS. Leads to excess uric acid formation, retardation, self-mutilation, aggression, hyperuricemia, gout, choreoathetosis
mental retardation, gout, choreoathetosis, hyperuricemia, aggression, and self-mutilation	Lesch Nyhan syndrome
Floroquinolones	inhibits bacterial gyrases/topoisomerases
Nucleotide excision repair defect	Xeroderma Pigmentosum
Mismatch repair defect	HNPCC
smallest RNA	tRNA
largest RNA	mRNA
Most abundant rna	rRNA
start codon	AUG (which codes for methionine)
stop codons	UGA, UAG, UAA
RNA polymerase synthesize which RNAs	1-rRNA, 2-mRNA, 3-tRNA
MOA of alpha amanitin	found in death cap mushrooms it inhibits RNA polymerase II and can lead to liver failure
AAUUAAA	signal for polyadenylation at the 5 prime end of RNA
anti spliceosomal scRNPs	SLE
aminoacyl transferase	important in attachment of new amino acid to the 3 prime end of tRNA.
Tetracyclines	binds 30S subunit and prevents the attachment of aminoacyl-tRNA
Aminoglycosides	inhibit the formation of the INITIATION COMPLEX, causing misreading of mRNA
Chloramphenicol	inhibits 50S PEPTIDYLTRANSFERASE
Macrolides	binds 50S to block TRANSLOCATION
Clindamycin	binds 50S to block TRANSLOCATION
prokaryotic ribosomal subunits	30S + 50S = 70S
Eukaryotic ribosomal subunits	40S + 60S = 80S
p53 and Rb	inhibits progression from G1to S
permanent cell types	neurons, skeletal and cardiac muscle, RBCs
Stable (quescent) cells	hepatocytes and lymphocytes and they enter G1 from G0 when stimulated
Labile	Never go into G0 and divide rapidly with a short G1, they are bone marrow, hair follicles, skin and gut epithelial cells
site of steroid synthesis	smooth ER
Site of drug detoxification	Smooth ER
Site of synthesis of secretory proteins and N-linked oligosaccharide additions to proteins	RER
sites rich in Smooth ER	hepatocytes and steroid producing adrenal cortical cells
Site of synthesis of cytoplasmic and organellar proteins	free ribosomes
this targets protein to the lysosome	mannose-6-phosphate
Drugs that act on microtubulues	1. mebendazole/thiabendazole (antihelminthic), 2. Grisofulvin (anti-fungal), 3. Vincristine/vinblastine (anti-neoplastic), 4. Paclitaxel, 5. Colchicine (anti-gout)
Chediak-Higashi Syndrome	microtubule depolarization defect: DECREASED PHAGOCYTOSIS, causing recurrent pyogenic infections, partial albinism, periph. neuropathy
Kartagener's Syndrome	immotile cilia due to dynein arm defect. Results in male/female infertility, bronchiectasis, recurrent sinusitis (can't sweep bacteria/particles out of airways), assc. w/ situs inversus
Ouabain	inhibits K+ binding on the Na/K ATPase
Cardiac glycosides (digoxin, digitoxin)	directly inhibit Na/K ATPase leading to indirect inhibition og Na/Ca exchange, increasing the Ca in the cell to INCREASE CARDIAC CONTRACTILITY.
Collagen	Type 1: Bone, Skin, Tendon, Type 2: Cartilage, Type 3: Reticulin (skin, blood vessels, uterus, fetal tissue), Type 4: Basement membrane
Osteogensis Imperfecta	AUTOSOMAL DOMINANT. Problem forming PROCOLLAGEN (three alpha chain coming together to form a helix). Multiple fractures, BLUE SCLERA. Type 1 collagen affected.
Scurvy	Vitamin C is required for the hydroxylation of the preprocollagen at specific lysine or proline residues.
Ehlers-Danlos	Problem with assembling tropocollagen into COLLAGEN FIBRILS. Type 3 collagen most affected, meaning BLEEDING, HYPEREXTENSIBLE SKIN, HYPERMOBILE JOINTS
Alport's Syndrome	X-LINKED RECESSIVE. Gene defects in Type 4 collagen, leading to progressive hereditary nephritis,
Collagen formation	Preprocollagen, procollagen, tropocollagen, collagen fibrils
I-cell diseases	inherited lysosomal storage disorder; failure of addition of M6P to lysosome proteins, leading to secretion of lysosomal enzymes. Coarse facial features, cloudy cornea, restricted joint movement, high plasma levels of lysosomal proteins. Often fatal in childhood.
Emphysema	alpha-1-antitrypsin deficiency causes increased degradation (or increased ELASTASE ACTIVITY) of lung elastin.
Southern Blot	DNA probe looking for DNA sequence
Northern Blot	DNA probe looking for RNA sequence
Western Blot	Antibody probe looking for protein of interest
ELISA	Antibody-Antigen reactivity
SNoW DRoP	Southern = DNA, Northern = RNA, Western = Protein
ddNTPs	Sanger sequencing
Cloning	production of recombinatn DNA molecule that is self-perpetuating
random insertion of gene into a mouse genome	constitutive
targeted insertion or deletion of a gene through homologous recombination with mouse gene	conditional
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Question	Answer
karyotype	metaphase chromosome are stained, ordered, and numbered according to morphology, size, arm length ratio and banding patter
Samples that karyotypes can be done on	blood, bone marrow, amniotic fluid, placental tissue
Karyotypes used to detect	chromosomal imbalances
	memorize

 

Autosomal dominant diseases

 

Question	Answer
Achondraplasia	defect inf FGFR3 resulting in dwarfism, short limbs, with normal head and trunk size, assoc with advanced paternal age
ADPKD	chromsome 16, bilateral polycyctic kidneys, assoc with berry aneurysm, liver cysts, and MVP; mutation in APKD1
Familial adenomatous polyposis	Chromosome 5 (5 letters in polyp), associated with a lot of polyps in colon that can progress to cancer unless resected
Familial hypercholestrolemia (hyperlipidemia type IIA)	high LDL levels due to absent or defective LDL receptor
Hereditary hemorrhagic telangiectasia	Osler-Weber-Rendu syndrome (multiple Atriovenous malformations, telangiectasias and skin discolorations and recurrent epistaxis
associated with ret gene	MEN 2A and 2B
NF1	von Recklinghausen disease on chromosome 17, cafe au lait spots, neural tumors, Lisch nodules which are pigmented iris hamartomas, scoliosis, optic pathway gliomas, pheochromocytoma, and increased tumor susceptibility
bilateral acoustic neuromas, juvenile cataracts on NF2 gene on chromosome 22	NF2
assoc with multiple bulateral renal cell carcinomas	VHL disease
VHL gene is located on this chromosome	chromosome 3
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associated with hemangioblastomas of the retina, cerebellum, and medulla

Question	Answer
ash leaf spots on skin	tuberous sclerosis
constitutive expression of HIF (transcription factor) and activation fo angiogenic growth factors	VHL disease
CAG repeat disorder located on chromosome 4	HD
CAG repeat disorder	Huntington's disease
X-linked fram shift mutation resulting in atrophy of muscles usually in pelvic girdle first, fibrofatty replacement of calves and requirement of upper extremities to stand up (Gower's maneuver)	Duchenne's Muscular dystrophy
deletion fo dystrophin gene	Duchenne's muscular dystrophy
longest human gene	Dystrophin (DMD)
X-linked mutated dystrophin gene with onset in adolescence or early adulthood	Becker's muscular dystrophy
diseases due Due to a trinucleotide repeat expansion	Huntington's, myotonic dystrophy, Fragile X syndrome, and Friedrich's ataxia (Try hunting for my Fried Eggs (X))
muscular dystrophy diagnosis	increase CPK and muscle biopsy
mental retardation, large jaw, large everted ears, and large testes, autism, MVP	Fragil X syndrome
mental retardation, large jaw, large everted ears, and large testes, autism, MVP and CGG trinucleotide repeat	fragile X syndrome
defect in methylation and expression fo FMR1 gene	fragile X syndrome
most often due to a deletion of phenylalanine in the 508 position on chromosome 7	Cystic fibrosis
disease caused by a defect in the CFTR gene	Cystic fibrosis
microencephaly, holoProsencephaly, Poludactyly, cleft lip/ Palate, microcephaly, mental retardation is severe	Patau's syndrome (trisomy 13)
Trisomy 13	Patau's syndrome
Trisomy 18	Edward's syndrome
Trisomy 21	Down's syndrome
Associated with advanced maternal age	Down's syndrome
Associated with advanced paternal age	Fragile X
pt presents with a simean crease, flat fascies, epicanthal folds, duodenal atresia	Down's syndrome
microcephaly, mod to severe mental retardation, high pitched crying, epicanthal folds, cardiac anomalies	Cru di Chat (chromosome 5 microdeletion on short (p) arm)
congenital microdeletion diseases	Cru-di-Chat and Williams syndrome
Elfin facies, mental retardation, hypercalcemia, well develop verbal skills, extreme friendliness to strangers	Williams syndrome caused by microdeletion on long arm (q) of chromosome 7
22q11 deletion syndrome characteristics	CAbnormal fascies Thymic aplasia Cardiac defects Hypocalcemia secondary to parathyroid aplasia -- CATCH 22
DiGeorge's syndrome	Thymic aplasia, parathyroid, cardiac anomalies due to defect in development of third and fourth branchial pouches
Velocardiofacial syndrome	palate, cardiac, and facial defects
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Question	Answer
the only purely ketogenic amino acids	leucine and lysine
pyruvate is involved in these metabolic pathways	alanine transfer of amino groups to liver, production of oxaloacetate via pyruvate carboxylase for gluconeogenesis fr TCA cycle, production of acetyl Coa and bridge to the TCA cycle from pyruvate dehydrogenase, production of lactate via lactate dehydrogenase(as end of anaerobic glycolysis)
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