PMID- 29971013
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20201001
IS  - 1664-042X (Print)
IS  - 1664-042X (Electronic)
IS  - 1664-042X (Linking)
VI  - 9
DP  - 2018
TI  - Exploring the Potential Roles of Band 3 and Aquaporin-1 in Blood CO(2) 
      Transport-Inspired by Comparative Studies of Glycophorin B-A-B Hybrid Protein 
      GP.Mur.
PG  - 733
LID - 10.3389/fphys.2018.00733 [doi]
LID - 733
AB  - The Cl(-)/HCO(3)(-) exchanger band 3 is functionally relevant to blood CO(2) 
      transport. Band 3 is the most abundant membrane protein in human red blood cells 
      (RBCs). Our understanding of its physiological functions mainly came from 
      clinical cases associated with band 3 mutations. Severe reduction in band 3 
      expression affects blood HCO(3)(-)/CO(2) metabolism. What could happen 
      physiologically if band 3 expression is elevated instead? In some areas of 
      Southeast Asia, about 1-10% of the populations express GP.Mur, a glycophorin 
      B-A-B hybrid membrane protein important in the field of transfusion medicine. 
      GP.Mur functions to promote band 3 expression, and GP.Mur red cells can be deemed 
      as a naturally occurred model for higher band 3 expression. This review first 
      compares the functional consequences of band 3 at different levels, and suggests 
      a critical role of band 3 in postnatal CO(2) respiration. The second part of the 
      review explores the transport of water, which is the other substrate for 
      intra-erythrocytic CO(2)/HCO(3)(-) conversion (an essential step in blood CO(2) 
      transport). Despite that water is considered unlimited physiologically, it is 
      unclear whether water channel aquaporin-1 (AQP1) abundantly expressed in RBCs is 
      functionally involved in CO(2) transport. Research in this area is complicated by 
      the fact that the H(2)O/CO(2)-transporting function of AQP1 is replaceable by 
      other erythrocyte channels/transporters (e.g., UT-B/GLUT1 for H(2)O; RhAG for 
      CO(2)). Recently, using carbonic anhydrase II (CAII)-filled erythrocyte vesicles, 
      AQP1 has been demonstrated to transport water for the CAII-mediated reaction, 
      CO(2(g)) + H(2)O right harpoon over left harpoon HCO(3)(-)((aq)) + H(+)((aq)). AQP1 is structurally associated 
      with some population of band 3 complexes on the erythrocyte membrane in an 
      osmotically responsive fashion. The current findings reveal transient interaction 
      among components within the band 3-central, CO(2)-transport metabolon (AQP1, band 
      3, CAII and deoxygenated hemoglobin). Their dynamic interaction is envisioned to 
      facilitate blood CO(2) respiration, in the presence of constantly changing 
      osmotic and hemodynamic stresses during circulation.
FAU - Hsu, Kate
AU  - Hsu K
AD  - Transfusion Medicine and Immunogenetics Laboratories, MacKay Memorial Hospital, 
      Tamsui, Taiwan.
LA  - eng
PT  - Journal Article
PT  - Review
DEP - 20180619
PL  - Switzerland
TA  - Front Physiol
JT  - Frontiers in physiology
JID - 101549006
PMC - PMC6018491
OTO - NOTNLM
OT  - CO2 transport
OT  - GP.Mur
OT  - aquaporin-1
OT  - band 3
OT  - erythrocytes
OT  - glycophorin
OT  - metabolon
EDAT- 2018/07/05 06:00
MHDA- 2018/07/05 06:01
PMCR- 2018/06/19
CRDT- 2018/07/05 06:00
PHST- 2018/03/28 00:00 [received]
PHST- 2018/05/25 00:00 [accepted]
PHST- 2018/07/05 06:00 [entrez]
PHST- 2018/07/05 06:00 [pubmed]
PHST- 2018/07/05 06:01 [medline]
PHST- 2018/06/19 00:00 [pmc-release]
AID - 10.3389/fphys.2018.00733 [doi]
PST - epublish
SO  - Front Physiol. 2018 Jun 19;9:733. doi: 10.3389/fphys.2018.00733. eCollection 
      2018.