SHELF review

• Phenylketonuria


  Phenylalanine buildup due to phenylalanine hydroxylase mutation; can occur when eating protein or any artificial sweeteners (aspartame); if recognized, can be managed by avoiding Phe
• Phenylketonuria


  • Intellectual disabilities, neurological symptoms, growth reduction, mousy urine color
• Lipofuscin


  Yellow-brown pigment showing undigested residues in neurons
• Lipofuscin


  • Macular degeneration; Alzheimer's; Parkinson's; cardiomyopathies/heart failure; atherosclerosis
• Steatosis


  Fat accumulation in liver cells. Can be due to obesity, metabolic syndromes, alcoholism, etc.
• Cobalamin (B12) deficiency


  Pernicious anemia
• Folic acid deficiency


  Megaloblastic anemia
• Pellagra


  Niacin (B3) deficiency; 3 D's = Dermatitis, diarrhea, dementia
• Beriberi


  Thiamine deficiency; Extreme lethargy (I cannot I cannot)
• Wernicke-Korsakoff


  Same as Beriberi but brought on by alcoholism
• Marfan's Syndrome


  • "tall/lanky" individuals, long limbs and spider-like fingers, chest abnormalities
• Ehlers-Danlos


  • Joint hypermobility, soft "velvet-like" skin, easy bruising, poor healing
• Ehlers-Danlos (vascular type)


  Effects blood vessels due to type 3 Collagen Mutations
• Nuclear Envelope


  Made of an outer and inner nuclear membrane separated by the perinuclear cisternae
• Nuclear Pores


  Gates that allow traffic in/out
• Nuclear Lamina


  Provides shape and stability, links chromatin to nuclear envelope
• Heterochromatin


  Tightly packed in interphase nucleus, NOT being transcribed, the visible genetic material on microscopy
• Euchromatin


  Loose, ACTIVELY transcribed
• Nucleolus


  Site of rRNA transcription and rRNA synthesis
• Membranes


  • They are not homogenous; in constant dynamic flux; asymmetric; shape determined by cytoskeleton

  
• Lipid Raft


  Associate with different proteins/signaling molecules
• Microfilaments


  • Actin; G-actin hydrolyzes ATP forms F; F-actin has + and - ends, and does adhesion, surface modifications (microvilli and stereocillia), movement and contraction; actin can branch
• Intermediate Filaments


  • Keratins, Vimentin, Neurofilament, Lamins, Beaded Filaments
• Microtubules


  • Have + (rapidly growing) and - (MTOC) ends; cell shape, transport; cilia and flagella, dynamic instability; Kinesin (toward + end), Dyenin (toward - end)
• Cell Cycle Stages


  • Prophase, Prometaphase, Metaphase, Anaphase, Telophase
• Interphase


  Period between cell divisions
• Mitotic Spindle


  Polar, kinetochore, astral MT's
• Smooth ER


  Lots in cells with lipid metabolism and steroid synthesis; sequesters Ca (sarcoplasmic reticulum in skeletal muscles); degrades toxins and synthesizes lipids
• Rough ER


  Ribosomes; post-translational modification of proteins; protein secreting cells; Nissl substance in neurons
• Golgi Apparatus


  Protein packaging and sorting; cis compartment (entrance) trans compartment (sorting and leaving)
• Lysosomal Storage Diseases


  • I cell disease - Golgi enzyme
  • Tay-Sachs - hexosaminidase A
  • Fabry - alpha galactosidase A
  • Gaucher - Beta glucocerebrosidase
  • Niemann-Pick - sphingomyelinase
• Peroxisomes


  Zellweger Syndrome - mutated peroxisome targeting signal. Long branched chain fatty acids that impair organ function. Plasmalogens affect brain and CNS
• Fluid Mosaic Model


  Membrane glycerophospholipids exhibit fluidity by 'sliding' past one another. They do NOT readily flip inner/outer but can move within a leaflet

  
• Alpha Helix


  • 3.6 AA per turn; To make an Alpha Helix you need 3 AA then hydrophobic followed by 4 AA then hydrophobic
• Beta Sheet


  • To make a Beta Sheet you need every other to be hydrophobic
• Reverse turns


  Initiated by Proline (called "helix-breaking)
• Protein Structure


  • Primary, Secondary, Tertiary, Quaternary Structure
• Sickle Cell Disease


  E6V → Hb 'clumps' cannot go through vessels as effectively; Stroke, infections, pain crises; Sickle Cell trait gives selective advantage against Malaria; Hydroxyurea; Bone Marrow Transplant; Blood Transfusions
• Cystic Fibrosis


  Phe508 Deletion → Cystic Fibrosis Transmembrane Conductance Regulator; Cannot pump CL and H2O out as effectively = buildup of Mucus in lungs (fatal); Trikafta
• Creutzfeldt-Jakob Syndrome (Mad Cow)


  Prion disease where PrPC becomes Beta Sheet. Amyloid deposits appear and cause nervous system complications; Eating Beef from England in the 1990's or methionine homozygosity at codon 129