Module 1: Part 4 Protein Flashcards
Insulin signaling pathway for GLUT4 transporters
Overall message
RTK pathway via PIP3 and Protein Kinase B (PKB)
Takeaway: Cascade pathways regulate availability/presence of nutrient specific transporters into cells
Structure of hemoglobin
2 alpha, 2 beta globin peptides and 4 heme groups
Distal Histidine is AA responsible for stabilizing oxygen
What is hydrolyzed protein
Amino acids
AA composition depends on source of the protein
Glutamic acid properties
- neurotransmitter involved in long term potentiation (learning and memory)
- Has been suggested to cause headaches, numbness and tingling sensation (as MSG)
What kinds of amino acids are naturally produced, produced by fermentation and produced synthetically?
Naturally occurring and fermented are produced as L amino acids
Synthetic manufactured AA produce D configuration as well (and can be isolated out)
How MSG occurs
Replace H on carboxyl group with Na and you have MSG
protein hydrolysate is MSG
And fermented foods produce MSG
How is histamine produced?
Histamine is produced via the decarboxylation of histidine
Histamine responses in the body
Mast cells produce histamine by decarboxylating histidine AA
Depending on receptor, histamine elicits cell specific response
1. Endothelial cells -> bronchial constriction and intestinal peristalsis
2. Parietal cells (HCl) –> increase epinephrine, pain and pruritus (itching)
3. Dendrites - neurotransmitter release
ex. histamine, norepinephrine, acetylcholine, peptides
Histamine signaling pathway in neurons
GPCR via PLC which produces IP3, IP3 binds ER to release Ca2+ as a signaling molecule, which binds to gated ion channels depolarizing the membrane of neuronal cell for augmented excitable signal
Symptoms experienced are painful
Case of PKU
Phenylketonuria - phenylalanine hydroxylase is lacking to convert Phe –> Tyr
Blood and brain levels of Phe rise, AA acid transporters to the brain are blocked and levels of AA decrease in the brain
- decreased protein synthesis, and neurotransmitter synthesis
- and other brain issues
Aspartame is
Aspartic acid + phenylalanine
Nutrasweet/Equal and E951
Can bind sweet taste receptors
RNA that acts as regulator of gene expression
microRNA
Short-lived, synthesized as needed and then degraded
Gout causes and symptoms
- joint inflammation due to high uric acid concentration in the body (a nucleotide metabolite)
- genetically predisposed or from high sugar diet
- may be due to high production or low disposal of uric acid
- uric acid in fluid around joints crystalizes causes pain and inflammation
Why are joints predisposed to gout?
Some cells have higher metabolic needs, such as nucleotide metabolites
High transporter concentration in the joints
Hypoxanthene accumulates and is converted to uric acid
