Drugs & Diseases Flashcards
Deficiency of Lysyl Hydroxylase, pro collagen peptidase
Stretchy skin, hyper mobile joints and weaken blood vessels
Mutation in AA sequences of collagen Type III (I or V)
Collagen not secreted; either degraded or accumulated
Ehlers-Danlos Syndrome
What are the causes of scurvy?
Vitamin C deficiency; ascorbate
No hydroxylation reactions; no cross-linking
Loose teeth, bruises on limbs; fragile capillaries
Problem behind Osteogenesis imperfecta Type I
Which type is Lethal?
Easy fracturing and bending of bones; 50% of collagen is normal
Null allele for pro-collagen alpha 1
Type II
Main disorder for Osteogenesis imperfecta Types II, III, and IV
Substitution of a Glycine with a more bulky Amino acid residue
No propagation of triple helix, mutations close to C-terminus more severe
Easy bending and fracturing of bones, slow wound healing and twisted spine
Expansion of CGG trinucleotide repeat in 5’UTR of FMR 1 gene
Also extensive methylation of FMR1 promoter
Most common form of mental retardation
Fragile X syndrome
Fragile X syndrome
Most common form of mental retardation
Expansion of CGG trinucleotide repeat in 5’UTR of FMR1 gene
Also extensive methylation of FMR1 promoter
Rett Syndrome
Inappropriate activation of methylated genes
Autism spectrum disorder mainly in females
Mutations in X linked MECP2 (methyl CpG binding protein 2) which normally binds and silences methylated genes
X-linked dominant; males miscarried, therefore mainly in females
Which syndrome causes inappropriate activation of methylated genes, caused by mutations in X linked MECP2 (methyl CpG binding protein 2) that normally binds and silences methylated genes
Rett Syndrome
X-linked dominant; mainly in females; males are miscarried
Alpha-amanitin “death cap” mushroom function
Binds euk RNA polymerase, inhibiting DNA tx
RNA pol II
Transcribes protein coding genes
Makes mRNA
Method of action for Rifampin
Binds to beta subunit of prok RNA polymerase
Stops transcription initiation
Used to treat tuberculosis
Action of Actinomycin D
Antibiotic
Inhibits Tx
Binds DNA template, not allowing for RNA pol to move along the strand
Tetracyclin
Streptomycin
Erythromycin
Chloramphenicol
All disrupt what process?
Prok Translation
Cyclohexamide
Pseudomonas toxin
Diphteria toxin
All inhibit which process?
Euk Translation
Method of action of Shigella toxin
Binds to A site on euk ribosome, preventing aminoacyl tRNA binding, thereby preventing protein synthesis in translation
Method of action of Shigella toxin
Binds to A site on euk ribosome, preventing aminoacyl tRNA binding, thereby preventing protein synthesis in translation
What are the two categories of chromosome abnormalities?
- Structural
2. Numerical
What are the categories for numerical chromosome abnormalities?
- Aneuploidy; single chromosomes (monosomy, trisomy, tetrasomy)
- Polyploidy; complete sets of chromosomes (triploidy, tetraploidy)
What are the categories of structural chromosome abnormalities?
- Translocation
- Inversion - two breaks in same chromosome w/ reversal of order of segment
- Deletion - results in unbalanced karyotype; partial monosomy; offspring will have too much info and not
- Insertion
- Rings
- Isochromosomes
Robertsonian Translocation
Two non-homologous Acrocentric chromosomes break at centromere and long arms fuse, while short arms are usually lost
No change in chrom. Number or risk to carriers
What cytogenetic abnormalities are most common in live born infants?
Trisomies XXY, XYY, and XXX