Erythropoiesis

Question 1

Erythryopoietin (EPO) is produced in the _____ by ______.

Answer 1

Produced in kidney by peritubular cells

Question 2

Development of red blood cells occurs in the?

Answer 2

Bone marrow

Question 3

Function of kidney in blood?

Answer 3

Sets a very fine balance between the number of red cells and the amount of plasma

Question 4

_____ drives EPO, and the kidney responds to this signal.

Answer 4

Hypoxic stress

Question 5

Describe hypoxic stress driving EPO production

Answer 5

Cells come into blood faster and appear larger, because they are reticulocytes and retain mRNA to make proteins

Question 6

How does body rescue red blood cells from apoptosis so their numbers amplify?

Answer 6

Interaction of EPO with EPO receptors (EPOR) on BFU-E and CFU-E allows them to rescue them from apoptosis.

Question 7

Describe EPO interaction with EPOR on BFU-E and CFU-E

Answer 7

Directly stimulates maturity of CFU-E, without it, they would apoptose after 1 cell cycle.

Question 8

EPO causes ______ of EPOR polypeptide

Answer 8

Homodimerization: a protein composed of two polypeptide chains that are identical in the order, number, and kind of their amino acid residues.

Question 9

Regulatory region of EPOR binds constitutively to?

Answer 9

Janus-activated kinase 2 (JAK2)

Question 10

Activation of the _______ signalling pathway allows for homodimerization of EPOR polypeptide

Answer 10

JAK2/STAT5

Question 11

Acquired mutations in the EPOR signalling pathway have been identified in?

Answer 11

PV, essential thrombocythemia and idiopathic myelofibrosis