Module 2 Vocab Flashcards
(102 cards)
1
Q
Lipid Bilayer
A
The membrane structure of the plasma membrane in a cell, ~ 5 nm thick
2
Q
Phopholipids
A
The basic component of the plasma membrane, is amphipathic witha hydrophillic head and hydrophobic tail
3
Q
Fluid mosaic model
A
Membrane model which suggests that proteins and lipids can move freely laterally in the membrane
4
Q
Membrane fluidity
A
Determines the ability of particles to move about in a membrane laterally
5
Q
FRAP
A
Fluorescence recovery after photobleaching; used to study membrane protein diffusion
6
Q
SPT
A
Single particle tracking microscopy; tracks the movement of a particel tagged with a gold flake
7
Q
Integral membrane proteins
A
Includes transmembrane, monolayer-associated, and lipid-linked proteins; proteins that are embedded into the membrane directly
8
Q
Peripheral Membrane Proteins
A
Only includes rotein attached proteins; proteins indirectly bound to the membrane
9
Q
Transmembrane domain
A
Portions of a protein that tend to form alpha helices with hydrophobic side chains, allowing them to span the membrane favorably
10
Q
Passive Transport
A
Transport through a cell that happens without the addition of energy
11
Q
Active Transport
A
Transport through a cell that requires teh addition of an energy source
12
Q
Diffusion
A
A form of passive transport that uses concentration gradients to move molecules
13
Q
Facilitated Diffusion
A
Passive transport of molecules through a channel in the membrane
14
Q
Rate of diffusion across a membrane
A
Dependent on molecule size, charge, solubility, membrane viscosity, concentration gradient, receptor/channel protein density, and cell temperature
15
Q
Osmosis
A
Movement of water from low to high solute concentration
16
Q
Isotonic
A
Concentration equilibrium or maintained
17
Q
Hypotonic
A
Dilute solution
18
Q
Hypertonic
A
Highly concentrated solution
19
Q
Coupled Transporter
A
Active transport method that moves a type of molecule out of the cell and at least one different molecule into the cell
20
Q
ATP-Driven pump
A
Uses ATP as an energy source to transport molecules against their concentration gradient into or out of a cell
21
Q
Light-driven pump
A
Uses energy from light to drive molecules against their electrochemical gradient
22
Q
Uniporter
A
Transports one molecule in one direction
23
Q
Symport
A
A type of coupled transport that co-transports different molecules
24
Q
Antiport
A
A type of coupled transporter that transport one molecule in and one out
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Coupled Transporter
Exploit the energy stored in electrochemical gradients of one solute to drive the pumping of another solute against its gradient
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ABC Transporters
ATP binding cassette transporters; use the energy of ATP hydrolysis to switch conformations
27
Signal Sequences (SS)
20-22 amino acid sequences located mostly at the N-terminus of proteins with a long hydrophoic stretch followed by a charged amino acid; indicates where a protein goes in the cell
28
Smooth endoplasmic reticulum (SER)
Synthesizes and secretes hormones, detoxifies organic compounds
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Sarcoplasmic reticulum
SER in muscle cells that stores and releases Ca++
30
Rough Endoplasmic
Site of synthesis of specific proteins
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Co-Translational Translocation
Protein enters the ER as it is being synthesized
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Post-Translational Translocation
Proteins that enter the ER after they are synthesized
33
Translocator Protein
A protein that binds to the signal sequence of a growing soluble protein and deposits it into the ER
34
Signal Peptidase
Cleaves the signal sequence of a protein following its translocation into the ER
35
Signal Recognition Particle (SRP)
A complex of 6 polypeptides and 1 cytoplasmic RNA that binds to the signal sequence; when bound to the SS temporarily halts translation
36
SRP Receptor
Binds to the SRP and allows the SS to complex with the protein translocator
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N-terminus
The terminus of the protein that faces the inside of the ER lumen
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Transmembrane Proteins
Proteins that span across the plasma membrane of a cell or organelle; part of their protein is in the cytoplasm, part in ER lumen during synthesis (N-terminus)
39
STOP Transfer Sequence
Transmembrane domains of proteins that halt their movement through a membrane during synthesis
40
Hydropathy Plot
A plot that shows the number of transmembrane domains in a protein
41
Disulfide Bonds
Proteins that are transported to the ER have them as the environment inside is oxidizing
42
Protein Disulfide Isomerase
Facilitate the formation of S-S bonds and can correct errors
43
Chaperone Proteins
Help to correctly fold proteins during and after synthesis
44
Self-fold
Proteins do this due to interactions between amino acid side chains and their surrounding medium
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Aggregates
Incorrectly folded proteins that are not proteolyzed grouped together; can be broken down by autophagocytosis
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Autophagocytosis
A recycling mechanism in the cell
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Ubiquitin
A sugar that is added to proteins to signal them for degradatino in the proteosome
48
Proteasome
A small vesicle link organelle responsible for protein degradation
49
Proteasome Mediated Degradation
An energy requiring process that recognizes ubiquitin sugar as a signal for degradation
50
Sugar Addition and Modification
Occurs in the ER and Golgi and is helpful in determining topology of membrane proteins in membranes, serves as binding sites, helps secreted and membrane proteins to fold, and protects membrane proteins from attack by proteases
51
Exocytosis
The process of transporting proteins and other cargo out of the cell; for proteins it goes from the ER to the Golgi and outward from there to the plasma membrane and is released from the cell
52
Golgi Body
Discovered by Camillo Golgi; modifies proteins by the sequential addition and removal of sugars and other post-translational modifications
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Golgi Stack
Comprised of the cis Golgi network (closest to ER), the cis cisterna, the medial cisterna, the trans cisterna, and the trans Golgi network
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Cis Glogi Network
Responsible for sorting proteins and for the phosporylation of oligosaccharides on lysosomal proteins
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cis cisterna
Responsible for the removal mannose sugars (Man)
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medial cisterna
Responsible for the removal an mannose sugars and the addition of N-Acetylglucosamine (GlcNAc)
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trans cisterna
Responsible for the addition of Galactose sugars (Gal) and NANA
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trans Golgi Network
Responsible for sorting, the suflation of tyrosines and carbohydrates, and sending proteins to their next location
59
Nuclear Pore Complex (NPC)
Responsible for transport of cargo into and out of the nucleus; 50-100 protein complex, with fibrils on the cytosol side, a basket inside, is a ring shape with 8-fold symmetry
60
Nuclear Pore
Molecules 60kD and smaller can diffuse through, but larger marcomolecules (larger proteins, RNA, and Ribosomes) must be transported through; proteins can be transported folded or unfolded
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Nuclear transport
Directed by nuclear pores and associated with regulatory proteins
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Nuclear Import
The import protein binds to NLS and passes through the NPC with Ran-GDP, then releases the protein and binds to Ran GTP to passes back through the NPC
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Nuclear Localization Sequence
A short stretch of amino acids the mediates the transport of nuclear proteins into the nucleus
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Ran GTPase
Most abundant small GTPase in the cell and functions as a molecular switch by converting between the active GTP and inactive GDP-bound conformations
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Nuclear Export
Export protein beinds the NES and Ran-GTP to pass through the NPC, releases both then passes back through the NPC
66
Green Fluorescent Protein (GFP)
A protein isolated from the Crystal Jellyfish Aqueora victoria; allows for the creation of fusion proteins to allow the identification of organelles or the tracking of proteins and protein activity in real time
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Fusion cDNA
To make this you fuse the sequence corresponding to the C-terminus of a selected protein with the N-terminus of the GFP making sure to maintain both reading frames and removing the selected proteins stop codon while retaining GFP's
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Restriction Enzymes
Proteins that cut specific sequences of nucleotides in dsDNA, can create sticky or blunt ends
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Sticky Ends
Allow for fusion of the ends of DNA sequences by making exposed nucleotides; ---|,,, '''|---
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Blunt Ends
Prevents fusion of the ends of DNA sequences; ---| |---
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Mitochondrial Matrix
Site of folding for mitochondrial proteins; surrounding by the inner mitochondiral membrane
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Mitochondria
"Power house of the cell lol"; an organelle with an outer plasma membrane and an inner membrane, with cytosol filling the intermembrane space
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Precusor Proteins
Unfolded proteins that are transported through the cytosol to the mitochondria
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Mitochondrial protein trafficking
Unfolded proteins are bound by their signal sequence to protein translocator in outer membrane, once the protein has begun to pass through a second protein translocater located on the inner membrane will bind to the signal sequence and transport the protein into the matrix
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Peroxisome
Responsible for digesting toxins and synthesizing phospholipids; most of its proteins are translocated from cytosol with a tripeptide signal sequence (Ser--Lys-Leu)
76
Zellwager Syndrome
Caused by mutations in genes that encode peroxisomal "import" protein; autosomal recessive
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Endosome
Plays a central role in vesicular transport into and out of cells
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Coated Vesicles
Vesicles with a coat of distinctive coat protiens; coat is shed once the vesicles buds from parent organ or cell structure
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Coat Proteins
Give shape to vesicles, recognize cargo proteins, and form specialized membrane patches/pits before budding
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Clathrin-coated Vesicles A
Originate in the Golgi apparatus and go to lysosomes via endosomes, coated with clathrin and adaptin 1
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Clathrin-coated Vesicles B
Originate at the plasma membrane and go to the endosomes, coated with clathrin and adaptin 2
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COPII-coated Vesicles
Originate in the ER and go to the Golgi cisterna, coated in COPII proteins
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COPI-coated vesicles
Originate in the Golgi cisterna and go to the ER, coated with COPI protein
84
Clathrin triskelion
Made of 3 clathrin subunits with the N-termini turning inwards; forms a sort of basket
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Adaptins
Proteins that bind clathrin to membranes by contacting the inner shell of the clathrin triskelion
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Invagination of Plasma membrane
Drive by the strucutre of clathrin allowing it to mediate endocytosis
87
Dynamin
A GTPase that facilitates the budding off of clathrin coated vesicles via constriction; causes GTP hydrolysis
88
LDL
Low-density lipoproteins; responsible for the transport of cholesterol (the bad cholesterol?)
89
Transcytosis
Endocytosis followed by exocytosis, permits movement of large molecules across epithelia
90
Rab-tethering protein
Binds to the exterior of vesicle and helps to direct recognition of the vesicle by the destination organelle
91
SNARE Proteins
A transmembrane protein that interfaces with a different version of itself to catalyze the fusion of the vesicle membrane with the organelle membrane
92
Botox
Forces muscle contraction by blocking Ca2++ channels in nerves
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Endocytosis
Plasma membrane invagination that forms vesicles that bud off into the cytoplasm
94
Pinocytosis
Non-specific endocytosis of fluids and small molecules
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Phagocytosis
Actin and receptor mediated endocytosis of large particulates and bacteria
96
Autophagy
Use of endocytic compartments to recycle cytosolic proteins and organelles
97
Lysosome
The result of a vesicle containing hydrolases fusing with an endosome; membrane bound sacs of at least 50 hydrolytic enzymes that digest both extracellular matter and intracellular decayed organelles; work at pH of 4.6 maintained by proton pump
98
Lysosomal Proteins
Marked by glycosylation in the ER with mannos-6-phosphate sugar and are transported to the trans Golgi network to be transported to lysosomes
99
Tay Sachs disease
Lysosomal storage disease resulting from beta-N-hexosamindase A deficiency, causes GM2 buildup in bloated lysosomes
100
Cystic Fibrosis Transmembrane Protein (CFTR)
Impair transport of CFTR protein from ER to plasma membrane, decreasing its prevalence slowing the transport of Cl- across plasma membrane resulting in pulmonary mucous thickening
101
Exosomes
Extracellular vesicles produced from multivesicular bodies; they are specialized endosomes that contain membrane-bound intraluminal vesicles
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