KEGG PATHWAY: mmu04973

PATHWAY: mmu04973

Entry

mmu04973                    Pathway

Name

Carbohydrate digestion and absorption - Mus musculus (house mouse)

Description

Dietary carbohydrate in humans and omnivorous animals is a major nutrient. The carbohydrates that we ingest vary from the lactose in milk to complex carbohydrates. These carbohydrates are digested to monosaccharides, mostly glucose, galactose and fructose, prior to absorption in the small intestine. Glucose and galactose are initially transported into the enterocyte by SGLT1 located in the apical brush border membrane and then exit through the basolateral membrane by either GLUT2 or exocytosis. In a new model of intestinal glucose absorption, transport by SGLT1 induces rapid insertion and activation of GLUT2 in the brush border membrane by a PKC betaII-dependent mechanism. Moreover, trafficking of apical GLUT2 is rapidly up-regulated by glucose and artificial sweeteners, which act through T1R2 + T1R3/alpha-gustducin to activate PLC-beta2 and PKC-beta II. Fructose is transported separately by the brush border GLUT5 and then released out of the enterocyte into the blood by GLUT2.

Class

Organismal Systems; Digestive system

Pathway map

mmu04973

Carbohydrate digestion and absorption

Other DBs

GO:	0044245 0001951

Organism

Mus musculus (house mouse) [GN:mmu]

Gene

100043207

Amy2a1; amylase 2a1 [KO:K01176] [EC:3.2.1.1]

100043684

Amy2a4; amylase 2a4 [KO:K01176] [EC:3.2.1.1]

100043686

Amy2a3; amylase 2a3 [KO:K01176] [EC:3.2.1.1]

100043688

Amy2a2; amylase 2a2 [KO:K01176] [EC:3.2.1.1]

109959

Amy2a5; amylase 2a5 [KO:K01176] [EC:3.2.1.1]

11651

Akt1; thymoma viral proto-oncogene 1 [KO:K04456] [EC:2.7.11.1]

11652

Akt2; thymoma viral proto-oncogene 2 [KO:K04456] [EC:2.7.11.1]

11722

Amy1; amylase 1, salivary [KO:K01176] [EC:3.2.1.1]

11928

Atp1a1; ATPase, Na+/K+ transporting, alpha 1 polypeptide [KO:K01539] [EC:7.2.2.13]

11931

Atp1b1; ATPase, Na+/K+ transporting, beta 1 polypeptide [KO:K01540]

11932

Atp1b2; ATPase, Na+/K+ transporting, beta 2 polypeptide [KO:K01540]

11933

Atp1b3; ATPase, Na+/K+ transporting, beta 3 polypeptide [KO:K01540]

11936

Fxyd2; FXYD domain-containing ion transport regulator 2 [KO:K01538]

12289

Cacna1d; calcium channel, voltage-dependent, L type, alpha 1D subunit [KO:K04851]

14377

G6pc1; glucose-6-phosphatase catalytic subunit 1 [KO:K01084] [EC:3.1.3.9]

14378

G6pc2; glucose-6-phosphatase, catalytic, 2 [KO:K01084] [EC:3.1.3.9]

14385

Slc37a4; solute carrier family 37 (glucose-6-phosphate transporter), member 4 [KO:K08171]

15275

Hk1; hexokinase 1 [KO:K00844] [EC:2.7.1.1]

15277

Hk2; hexokinase 2 [KO:K00844] [EC:2.7.1.1]

18706

Pik3ca; phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha [KO:K00922] [EC:2.7.1.153]

18707

Pik3cd; phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit delta [KO:K00922] [EC:2.7.1.153]

18708

Pik3r1; phosphoinositide-3-kinase regulatory subunit 1 [KO:K02649]

18709

Pik3r2; phosphoinositide-3-kinase regulatory subunit 2 [KO:K02649]

18710

Pik3r3; phosphoinositide-3-kinase regulatory subunit 3 [KO:K02649]

18751

Prkcb; protein kinase C, beta [KO:K19662] [EC:2.7.11.13]

18795

Plcb1; phospholipase C, beta 1 [KO:K05858] [EC:3.1.4.11]

18796

Plcb2; phospholipase C, beta 2 [KO:K05858] [EC:3.1.4.11]

18797

Plcb3; phospholipase C, beta 3 [KO:K05858] [EC:3.1.4.11]

18798

Plcb4; phospholipase C, beta 4 [KO:K05858] [EC:3.1.4.11]

20526

Slc2a2; solute carrier family 2 (facilitated glucose transporter), member 2 [KO:K07593]

20537

Slc5a1; solute carrier family 5 (sodium/glucose cotransporter), member 1 [KO:K14158]

212032

Hk3; hexokinase 3 [KO:K00844] [EC:2.7.1.1]

216019

Hkdc1; hexokinase domain containing 1 [KO:K00844] [EC:2.7.1.1]

226413

Lct; lactase [KO:K01229] [EC:3.2.1.108 3.2.1.62]

232714

Mgam; maltase-glucoamylase [KO:K12047] [EC:3.2.1.20 3.2.1.3]

232975

Atp1a3; ATPase, Na+/K+ transporting, alpha 3 polypeptide [KO:K01539] [EC:7.2.2.13]

23797

Akt3; thymoma viral proto-oncogene 3 [KO:K04456] [EC:2.7.11.1]

242851

Gnat3; G protein subunit alpha transducin 3 [KO:K19729]

27222

Atp1a4; ATPase, Na+/K+ transporting, alpha 4 polypeptide [KO:K01539] [EC:7.2.2.13]

333669

Gm5134; predicted gene 5134 [KO:K14158]

545562

Amy2b; amylase 2b [KO:K01176] [EC:3.2.1.1]

56485

Slc2a5; solute carrier family 2 (facilitated glucose transporter), member 5 [KO:K08143]

638904

Mgam2-ps; maltase-glucoamylase 2, pseudogene [KO:K12047] [EC:3.2.1.20 3.2.1.3]

67821

Atp1b4; ATPase Na+/K+ transporting, beta 4 polypeptide [KO:K01540]

68401

G6pc3; glucose 6 phosphatase, catalytic, 3 [KO:K01084] [EC:3.1.3.9]

69983

Sis; sucrase isomaltase [KO:K01203] [EC:3.2.1.48 3.2.1.10]

74769

Pik3cb; phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit beta [KO:K00922] [EC:2.7.1.153]

83770

Tas1r2; taste receptor, type 1, member 2 [KO:K04625]

83771

Tas1r3; taste receptor, type 1, member 3 [KO:K04626]

98660

Atp1a2; ATPase, Na+/K+ transporting, alpha 2 polypeptide [KO:K01539] [EC:7.2.2.13]

Compound

C00011

CO2

C00031

D-Glucose

C00033

Acetate

C00076

Calcium cation

C00089

Sucrose

C00092

D-Glucose 6-phosphate

C00095

D-Fructose

C00124

D-Galactose

C00163

Propanoate

C00165

Diacylglycerol

C00208

Maltose

C00238

Potassium cation

C00243

Lactose

C00246

Butanoic acid

C00282

Hydrogen

C00369

Starch

C00707

Xylan

C00714

Pectin

C00760

Cellulose

C01330

Sodium cation

C01355

Fructan

C01835

Maltotriose

C02049

Limit dextrin

C05981

Phosphatidylinositol-3,4,5-trisphosphate

C08822

Gum arabic

C12284

Saccharin sodium anhydrous

C12285

Sucralose

Reference

PMID:16586532

Authors

Drozdowski LA, Thomson AB

Title

Intestinal sugar transport.

Journal

World J Gastroenterol 12:1657-70 (2006)
DOI:10.3748/wjg.v12.i11.1657

Reference

PMID:14642859

Authors

Wright EM, Martin MG, Turk E

Title

Intestinal absorption in health and disease--sugars.

Journal

Best Pract Res Clin Gastroenterol 17:943-56 (2003)
DOI:10.1016/S1521-6918(03)00107-0

Reference

PMID:18393659

Authors

Kellett GL, Brot-Laroche E, Mace OJ, Leturque A

Title

Sugar absorption in the intestine: the role of GLUT2.

Journal

Annu Rev Nutr 28:35-54 (2008)
DOI:10.1146/annurev.nutr.28.061807.155518

Reference

PMID:19001049

Authors

Mace OJ, Lister N, Morgan E, Shepherd E, Affleck J, Helliwell P, Bronk JR, Kellett GL, Meredith D, Boyd R, Pieri M, Bailey PD, Pettcrew R, Foley D

Title

An energy supply network of nutrient absorption coordinated by calcium and T1R taste receptors in rat small intestine.

Journal

J Physiol 587:195-210 (2009)
DOI:10.1113/jphysiol.2008.159616

Reference

PMID:16186415

Authors

Kellett GL, Brot-Laroche E

Title

Apical GLUT2: a major pathway of intestinal sugar absorption.

Journal

Diabetes 54:3056-62 (2005)
DOI:10.2337/diabetes.54.10.3056

Reference

PMID:20522896

Authors

Goodman BE

Title

Insights into digestion and absorption of major nutrients in humans.

Journal

Adv Physiol Educ 34:44-53 (2010)
DOI:10.1152/advan.00094.2009

Reference

PMID:17222166

Authors

Wright EM, Hirayama BA, Loo DF

Title

Active sugar transport in health and disease.

Journal

J Intern Med 261:32-43 (2007)
DOI:10.1111/j.1365-2796.2006.01746.x

Reference

PMID:12512027

Authors

Santer R, Hillebrand G, Steinmann B, Schaub J

Title

Intestinal glucose transport: evidence for a membrane traffic-based pathway in humans.

Journal

Gastroenterology 124:34-9 (2003)
DOI:10.1053/gast.2003.50009

Reference

PMID:11562503

Authors

Stumpel F, Burcelin R, Jungermann K, Thorens B

Title

Normal kinetics of intestinal glucose absorption in the absence of GLUT2: evidence for a transport pathway requiring glucose phosphorylation and transfer into the endoplasmic reticulum.

Journal

Proc Natl Acad Sci U S A 98:11330-5 (2001)
DOI:10.1073/pnas.211357698

Reference

PMID:15546855

Authors

Wright EM, Loo DD, Hirayama BA, Turk E

Title

Surprising versatility of Na+-glucose cotransporters: SLC5.

Journal

Physiology (Bethesda) 19:370-6 (2004)
DOI:10.1152/physiol.00026.2004

Reference

PMID:12750891