Lecture 14

Question 1

genes for many growth factors or their receptors are _______; encode transcription factors

Answer 1

proto-oncogenes

Question 2

activation of _____ leads to hetero/homodimerization, phosphorylation of specific tyrosine residues, and recruitment of several proteins at the intracellular portion of the receptors

Answer 2

Epidermal growth factor (EGF) signaling

Question 3

chronic relapsing intestinal inflammation seen in the two types of autoimmune diseases ulcerative colitis and crohn’s disease; TNF-alpha plays key role in in the chronic inflammation; can be treated with monoclonal antibodies

Answer 3

inflammatory bowel disease

Question 4

complex process where skin or other tissue repairs itself after injury; divided into 4 sequential overlapping phases

Answer 4

wound healing

Question 5

naturally occurring substance capable of stimulating cellular growth, proliferation, and differentiation. signal by generally binding to a specific cell surface receptor on the surface of susceptible cells. play a critical role in embryonic growth, cell survival, and in wound healing in adults.

Answer 5

growth factors

Question 6

_____ mediates death pathways

Answer 6

TNF (tumor necrosis factor)

Question 7

SMADs are part of _______ signaling

Answer 7

TGF-B

Question 8

the _______ pathway serves to initiate a SMAD-dependent intracellular signaling cascade that activates or inhibits gene transcription

Answer 8

canonical or classical

Question 9

____ involves chronic inflammation; due to TNF-alpha growth factor

Answer 9

Rheumatoid arthritis

Question 10

within minutes post-injury, platelets aggregate at the injury site to form a fibrin clot which acts to control bleeding.

Answer 10

hemostasis phase

Question 11

T/F: a single growth factor regulates the salivary gland morphogenesis process

Answer 11

False; multiple expressed spatially and temporally

Question 12

angiogenesis, collagen deposition, granulation tissue formation, epithelialization, and wound contraction.

Answer 12

proliferative phase

Question 13

majority of growth factors are translated as a proform and then undergo proteolytic processing steps by members of the _________

Answer 13

proprotein convertase family of enzymes

furin is the most studied of these

Question 14

collagen is remodeled and realigned along tension force lines and cells no longer needed are removed by apoptosis.

Answer 14

remodeling phase

Question 15

______ are active as hetero or homodimers; initially bind to a specific type 2 receptor subunit which recruits a type 1 receptor subunit

Answer 15

TGF-Beta ligand

Question 16

activates genes promoting survival and apoptosis

Answer 16

nerve growth factor (NGF) signaling

Question 17

recombinant fusion protein between the TNF alpha receptor and the constant region of the IgG1 antibody; binds to TNF-alpha and prevent its cellular action; used to treat Rheumatoid arthritis

Answer 17

Etanercept (enbrel)

Question 18

growth factors are restricted _______ and _______ to prevent proliferative growth (tumors)

Answer 18

temporally; spatially

Question 19

T/F: Not all growth factors stimulate growth

Answer 19

True

Question 20

bacteria and debris are phagocytosed and removed from the wound site. Factors are released that cause migration and division of cells involved in the proliferative phase.

Answer 20

inflammatory phase

Question 21

2 major types of growth factors

Answer 21

protein and steroids

Question 22

T/F: Growth factor signaling involves binding to a cell membrane receptor and activating various intracellular signaling pathways

Answer 22

True

Question 23

T/F: Myostatin is a member of the EGF family

Answer 23

False; TGF-B

Question 24

caused by a mutation in the TGF-b receptor1 and TGF-b receptor2. Autosomal dominant mutation causing main features e.g., widely spaced eyes, cleft palate or bifid uvula, and aortic aneurysms.

Answer 24

Loeys-Dietz syndrome

Question 25

Type _____ TGF-B receptor is a serine/threonine kinase; binding results in phosphorylation of the recruited type ____ receptor

Answer 25

2;1

Question 26

one of the largest groups of cell regulatory proteins

Answer 26

TGF-Beta superfamily

Question 27

autosomal dominant mutation in TGF-b1 causing progressive diaphyseal dysplasia (hyperostosis and sclerosis of diaphyses of long bones).

Answer 27

Camurati-Engelmann disease

Question 28

four sequential overlapping phases of wound healing:

Answer 28

1. hemostasis, 2. inflammatory; 3. proliferative; and 4. remodeling.