Mannose 6-phosphate: Difference between revisions

{{Chembox

| Watchedfields = changed

| verifiedrevid = 450950432

| ImageFile = Mannose-6-phosphate.svg

| ImageSize =

| IUPACName =6-''O''-Phosphono-<small>D</small>-mannopyranose

| OtherNames =

|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|??}}

| CASNo = 3672-15-9

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = U2S53JF879

| PubChem = 65127

| ChEBI_Ref = {{ebicite|correct|EBI}}

| SMILES = C(C1C(C(C(C(O1)O)O)O)O)OP(=O)(O)O

| MeSHName = mannose-6-phosphate

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID_Comment = Unspecified anomers

| SMILES2 = O=P(O)(O)OC[C@H]1OC(O)[C@@H](O)[C@@H](O)[C@@H]1O

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| ChemSpiderID1 = 394282

| ChemSpiderID1_Comment = alpha anomer

| ChemSpiderID1_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID2 = 388338

| ChemSpiderID2_Comment = beta anomer

| ChemSpiderID2_Ref = {{chemspidercite|correct|chemspider}}

}}

|Section2={{Chembox Properties

| Formula = C₆H₁₃O₉P

| MolarMass = 260.136 g/mol

| Appearance =

| Density =

| MeltingPt =

| BoilingPt =

| Solubility =

}}

|Section3={{Chembox Hazards

| MainHazards =

| FlashPt =

| AutoignitionPt =

}}

'''Mannose-6-phosphate''' ('''M6P''') is a molecule bound by [[lectin]] in the [[immune system]]. M6P is converted to [[fructose 6-phosphate]] by [[mannose phosphate isomerase]].

M6P is a key targeting signal for [[acid hydrolase]] [[protein precursor|precursor proteins]] that are destined for transport to [[lysosome]]s. The M6P tag is added to such proteins in the ''cis''-[[Golgi apparatus]]. Specifically, in a reaction involving [[uridine diphosphate]] (UDP) and [[N-acetylglucosamine|''N''-acetylglucosamine]], the enzyme [[N-acetylglucosamine-1-phosphate transferase]] catalyzes the [[N-linked glycosylation|''N''-linked glycosylation]] of [[asparagine]] residues with M6P. Once appropriately marked with the M6P targeting signal, these proteins are moved to the ''trans''-Golgi network. There, the M6P [[Moiety (chemistry)|moiety]] is recognized and bound by [[mannose 6-phosphate receptor]] (MPR) proteins at pH 6.5–6.7.<ref name=Alberts>{{cite book|last=Alberts|first=Bruce|title=Molecular biology of the cell|year=2002|publisher=Garland Science|location=New York|isbn=978-0-8153-3218-3|edition=4th|display-authors=etal}}</ref>

The M6P-tagged lysosomal enzymes are shipped to the late [[endosomes]] via vesicular transport.<ref name=Alberts /> [[Enzyme replacement therapy]] (ERT) for several [[lysosomal storage diseases]] relies on this pathway to efficiently direct synthetic enzymes to the lysosome where each can metabolize its particular substrate.<ref name = Coutinho>{{cite journal |title= Mannose-6-phosphate pathway: A review on its role in lysosomal function and dysfunction|last1=Coutinho|first1= MF|last2=Prata|first2=MJ|date=2011-12-15|doi=10.1016/j.ymgme.2011.12.012 |pmid= 22266136|publisher=Elsevier|volume=105|issue= 4|journal=Molecular Genetics and Metabolism|pages=542–550}}</ref> The pH in the late endosome can reach 6.0, which causes dissociation of M6P from its receptor.<ref name=Alberts /> Upon release, the enzymes are ferried to their final destination in the lysosomes.<ref name=Alberts /> The MPRs are packed into vesicles that bud off the late endosome and return to the ''trans''-Golgi network.<ref name=Alberts /> In this way, the MPRs can be recycled.

* [[Insulin-like growth factor 2 receptor]]

* [[Mannose]]

==References==

<references />

{{Fructose and galactose metabolic intermediates}}