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Flashcards in Kapitel 12 Deck (68)
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1

Endoplasmic reticulum (ER)-resident chaperone protein member of the family of hsp70-type chaperone proteins.

BiP

2

Carbohydrate-binding chaperone protein in the endoplasmic reticulum (ER) membrane that binds to oligosaccharides on incompletely folded proteins and retains them in the ER.

calnexin

3

Carbohydrate-binding chaperone protein in the endoplasmic reticulum (ER) lumen that binds to oligosaccharides on incompletely folded proteins and retains them in the ER.

calreticulin

4

Organelle in green algae and plants that contains chlorophyll and carries out photosynthesis. A specialized form of plastid.

chloroplast

5

Occurring as translation proceeds. Examples include the import of a protein into the endoplasmic reticulum before the polypeptide chain is completely synthesized (co-translational translocation - Figure 12–32) - and the folding of a nascent protein into its secondary and tertiary structure as it emerges from a ribosome. (Figure 6–79)

co-translational

6

Contents of a cell that are contained within its plasma membrane but - in the case of eukaryotic cells - outside the nucleus.

cytoplasm

7

Contents of the main compartment of the cytoplasm - excluding membrane-bounded organelles such as endoplasmic reticulum and mitochondria.

cytosol

8

Isoprenoid lipid molecule that anchors the precursor oligosaccharide in the endoplasmic reticulum membrane during protein glycosylation.

dolichol

9

Labyrinthine membrane-bounded compartment in the cytoplasm of eukaryotic cells - where lipids are synthesized and membrane-bound proteins and secretory proteins are made. (Figure 12–33)

endoplasmic reticulum (ER)

10

Space enclosed by the membrane of the endoplasmic reticulum (ER).

ER lumen

11

Protein that remains in the endoplasmic reticulum (ER) or its membranes and carries out its function there - as opposed to proteins that are present in the ER only in transit.

ER resident protein

12

Short amino acid sequence on a protein that prevents it from moving out of the endoplasmic reticulum (ER). Found on proteins that are resident in the ER and function there.

ER retention signal

13

N-terminal signal sequence that directs proteins to enter the endoplasmic reticulum (ER). Cleaved off by signal peptidase after entry.

ER signal sequence

14

Membrane proteins anchored in the endoplasmic reticulum (ER) membrane by a single transmembrane α helix contained at their C-terminus.

ER tail-anchored proteins

15

Ribosome that is free in the cytosol - unattached to any membrane.

free ribosome

16

Movement of proteins between the cytosol and the nucleus through nuclear pore complexes in the nuclear envelope that function as selective gates.

gated transport

17

Any protein with one or more saccharide or oligosaccharide chains covalently linked to amino acid side chains. Most secreted proteins and most proteins exposed on the outer surface of the plasma membrane are glycoproteins.

glycoprotein

18

Mitochondrial membrane that encloses the matrix space and forms extensive invaginations called cristae.

inner membrane

19

Mitochondrial membrane that encloses the matrix space and forms extensive invaginations called cristae.

inner mitochondrial membrane

20

One of two concentric membranes comprising the nuclear envelope; contnuous with the outer nuclear membrane; contains specific proteins as anchoring sites for chromatin and the nuclear lamina.

inner nuclear membrane

21

Compartment of mitochondrion formed between the two concentric mitochondrial membranes.

intermembrane space

22

Large internal compartment of the mitochondrion.

matrix space

23

Ribosome attached to the cytosolic face of the endoplasmic reticulum. The site of synthesis of proteins that enter the endoplasmic reticulum. (Figure 12–38)

membrane-bound ribosome

24

Small vesicle derived from endoplasmic reticulum that is produced by fragmentation when cells are homogenized. (Figure 12–34)

microsome

25

Part of a multisubunit protein assembly bound to the matrix side of the TIM23 complex that acts as a motor to pull mitochondrial precursor proteins into the matrix space.

mitochondrial hsp70

26

Proteins first fully synthesized in the cytosol and then translocated into mitochondrial subcompartments as directed by one or more signal sequences.

mitochondrial precursor proteins

27

Membrane-bounded organelle - about the size of a bacterium - that carries out oxidative phosphorylation and produces most of the ATP in eukaryotic cells. (Figure 1–28)

mitochondrion (plural mitochondria)

28

Double membrane (two bilayers) surrounding the nucleus. Consists of an outer and inner membrane and is perforated by nuclear pores. The outer membrane is continuous with the endoplasmic reticulum. (Figures 4–9 and 12–7)

nuclear envelope

29

Bind to both the export signal and nuclear pore complex proteins to guide their cargo through the nuclear pore complex to the cytosol.

nuclear export receptors

30

Sorting signal contained in the structure of molecules and complexes - such as nuclear RNPs and new ribosomal subunits - that are transported from the nucleus to the cytosol through nuclear pore complexes. (Figure 12–13)

nuclear export signal