Home Page for S100A8

S100A8/MRP-8

Primary information about S100A8/MRP-8:
Basic chemical and physical information	Basic biological information	Basic genomic information	Metal ion binding constants	Interspecies sequence alignment	Information on function
Summary of structural studies	Information on the conformational change	List of available structures	Information about mutations	References about S100A8	Other web resources about S100A8
Additional information about S100A8/MRP-8:
Information about the evolutionary relationship of S100A8/MRP-8 to other proteins

Basic Information

Basic Chemical and Physical Information:
Additional names and abbreviations:	S100A8: cystic fibrosis antigen (in complex with S100A9); p23 (in complex with S100A9); calprotectin (in complex with S100A9); calgranulin A; L1 light chain; CP-10
Isoforms:	No information about isoforms is stored in the database
Yeast Protein Database Entries:	No links to the YPD are stored in the database

Number of amino acids:	88 (Rattus norvegicus) - 122 (Mus musculus) View a list of all sources stored in the database
Molecular weight:	10.079 kD (Rattus norvegicus) - 13.673 kD (Mus musculus) View a list of all sources stored in the database
pI:	experimental pI (Homo sapiens) = 6.7 (InfoCard)
Number of functional calcium binding sites:	not yet available in the data library
Macroscopic calcium binding constants:	not yet available in the data library
Other metal binding constants:	not yet available in the data library
Protein stability:	not yet available in the data library
Post-translational modifications:	not yet available in the data library

Basic Biological Information:
Source organisms:	Homo sapiens, Mus musculus, Rattus norvegicus View an annotated list of all sources stored in the database
Tissues:	Homo sapiens: monocytes (InfoCard) Homo sapiens: neutrophils (InfoCard) Homo sapiens: keratinocytes (InfoCard)
Subcellular localization:	not yet available in the data library
Regulation:	not yet available in the data library

Genomic Information:
GenBank entries:	View a list of GenBank entries stored in the database
Gene length:	not yet available in the data library
Gene structure:	not yet available in the data library
Promoter:	not yet available in the data library
Gene copies:	not yet available in the data library
Alleles:	no alleles are currently stored in the data library
Chromosomal localization:	Homo sapiens, expressed (GenBank code A12022): q21 region of chromosome 1 (part of the cluster of S100 protein genes) (InfoCard)

Interspecies Sequence Alignment


 
                    |-helixA-|--loop1------|helixB| 
                     En**nn**nX**Y*Z**#Ix**zn**nn*n 

HUMAN   :  MLTELEKALNSIIDVYHKYSLIKGNFHAVYRDDLKKLLETECPQYIRKK
MOUSE   :   PSELEKALSNLIDVYHNYSNIQGNHHALYKNDFKKMVTTECPQFVQNI
RAT     :   ATELEKALSNVIEVYHNYSGIKGNHHALYRDDFRKMVTTECPQFVQNK
BOVINE  :  MLTDLEXAIDSLIDVYHKYSLXKGNYHAVYXDDLKXLLETE


          |-helixC-|--loop2-----|helixD|
           En**nn**nX*Y*ZG#Ix**zn**nn*n
 
HUMAN   :  GADVWFKELDINTDGAVNFQEFLILVIKMGVAAHKKSHEESHKE
MOUSE   :  NIENLFRELDINSDNAINFEEFLAMVIKVGVASHKDSHKE
RAT     :  NTESLFKELDVNSDNAINFEEFLALVIRVGVAAHKDSHKE

The bovine MRP-8 is only sequenced through residue 41, but there is evidence suggesting that it is approximately 10 kD, making it similar in size to MRP-8 in other species.

Sequence alignment of the entire S100 subfamily

Functional Information:

General information:

no general functional information is currently stored in the database

Biological roles:

termination of cellular metabolic events: may be involved in this process by inhibiting the activity of casein kinase II (This function may be important in neutrophils, which have a sharply determined life span)
biochemical evidence in Homo sapiens: A purified protein complex containing S100A8/S100A9 was shown to inhibit the activity of casein kinases I and II (InfoCard)
chemotaxis: chemotactic factor (This function has been shown for the mouse protein. Human MRP-8 may also function extracellularly as a chemotactic factor, a function which may be inhibited when MRP-8 forms a complex with MRP-14)
biochemical evidence in Mus musculus: CP-10, the mouse homolog of S100A8, was isolated on the basis of its abiliuty to demonstrate chemotactic activity (InfoCard)
inflammation signal transduction pathway: interacts with arachidonic acid
biochemical evidence in Homo sapiens: The complex of S100A8 and S100A9 binds to arachidonic acid, the metabolites of which are involved in inflammation (InfoCard)

Disease states:

cystic fibrosis
in vivo evidence : The complex of S100A8 and S100A9 is the cystic fibrosis antigen, which is present in the serum of cystic fibrosis homozygotes, and in lower levels in the serum of clinically unaffect heterozygotes (InfoCard)
rheumatoid arthritis
in vivo evidence : The complex of S100A8 and S100A9 is found in the serum of patients with rheumatoid arthritis (InfoCard)

Target molecules:

S100A9
biochemical evidence for interaction in Homo sapiens: S100A8 and S100A9 were shown to form specific heterodimers by chemical cross-linking (InfoCard)
spectroscopic evidence for interaction in Homo sapiens: Changes were observed in the circular dichroism, fluorescence emission, and nuclear magnetic resonance spectra when S100A9 was mixed with S100A8 (InfoCard)
arachidonic acid
biochemical evidence for interaction in Mus musculus: The heterodimer of S100A8 and S100A9 was shown to ind arachidonic acid in a calcium-dependent manner by using radioactively labelled arachidonic acid (InfoCard)

Structural Information:

Calcium-coordination:

not yet available in the data library

Nature of the conformational changes:

not yet available in the data library

Secondary structure:
(as reported in the PDB file and its accompanying reference)

not yet available in the data library

Additional structural information:

no additional structural information is currently stored in the database

Available structures:
(follow the links from the PDB code to the retrieve the PDB files)

no structures are currently stored in the database

Information about mutants:

no mutants are currently stored in the database

Calcium-coordination:
not yet available in the data library

Nature of the conformational changes:
not yet available in the data library

Secondary structure: (as reported in the PDB file and its accompanying reference)
not yet available in the data library

Additional structural information:
no additional structural information is currently stored in the database

Available structures: (follow the links from the PDB code to the retrieve the PDB files)
no structures are currently stored in the database