Selected-GenAtlas references	SOURCE	GeneCards	NCBI Gene	Swiss-Prot	Ensembl
	HGNC	UniGene	Nucleotide	OMIM	UCSC

Home Page

FLASH GENE

Symbol

HP

contributors: mct/npt - updated : 17-12-2009

HGNC name	haptoglobin
HGNC id	5141

FLASH GENE DNA RNA EXPRESSION PROTEIN DISORDER ANIMAL & CELL MODELS

RNA

TRANSCRIPTS	type

text	three main alleles

identification nb exons type bp product Protein kDa AA specific expression Year Pubmed NM_001126102 5 - 1284 NP_001119574 38 347 - Van der Straten, Tripathi (2009) variant 3 - - - isoform 3 - ? - Tripathi (2009) also called alpha 1F-beta NM_005143 7 - 1461 NP_005134 - 406 - Van der Straten, Tripathi (2009) alpha 2 partial duplication of alpha 1

EXPRESSION

Type	restricted

constitutive of

expressed in	(based on citations)
organ(s)	System Organ level 1 Organ level 2 Organ level 3 Organ level 4 Level Pubmed Species Stage Rna symbol Digestive liver       highly Reproductive female system ovary       Visual eye anterior segment cornea

tissue

System Tissue Tissue level 1 Tissue level 2 Level Pubmed Species Stage Rna symbol Muscular striatum skeletal

cell lineage

cell lines

fluid/secretion

at STAGE

PROTEIN

PHYSICAL PROPERTIES

STRUCTURE

motifs/domains	N-terminal AA sequence has striking similarities to the light chain of human gamma-globulins (Tripathi 2009)
	a short consensus repeat
	a peptidase S1 domain
	growth factor-like repeats
	2 sushi structures (see F13B, SRCP1)
	only the beta-chain of haptoglobin is involved in receptor recognition (Cd163) (Nielsen 2007)

secondary structure

mature HPs are heterodimeric plasma glycoproteins composed of alpha- and beta-polypeptide chains that are covalently associated by disulfide bonds and in which only the beta-chain is glycosylated (Tripathi 2009)

conjugated

GlycoP

mono polymer

heteromer , tetramer

isoforms

Precursor

including alpha (1 or 2,84/143AAs) and beta chains (244AAs)

HOMOLOGY

interspecies

homolog to murine Hp

Homologene

FAMILY

peptidase S1 family

CATEGORY

transport carrier

SUBCELLULAR LOCALIZATION

extracellular

basic FUNCTION	combines with free plasma hemoglobin, preventing loss of iron through the kidneys and protecting the kidneys from damage by hemoglobin, while making the hemoglobin accessible to degradative enzymes
	binds the apolipoprotein (Apo) A-I domain, which is involved in stimulating the enzyme lecithin-cholesterol acyltransferase (LCAT) for cholesterol esterification (Salvatore 2009)
	protects Hb when oxidatively challenged with H(2)O(2) preserving CD163-mediated Hb clearance under oxidative stress conditions (Buehler 2009)

CELLULAR PROCESS

PHYSIOLOGICAL PROCESS

PATHWAY

metabolism

signaling

a component	heterotetramer alpha 2/beta 2 complexing with free oxyhemoglobin to be removed and degraded in liver
	dimer of alphabeta-chains covalently linked by a disulphide bond between the Cys15 residue of each alpha-chain (Polticelli 2008)

INTERACTION

DNA

RNA

small molecule

protein

binding free oxyhemoglobin

cell & other

REGULATION

ASSOCIATED DISORDERS

corresponding disease(s)

HP

Susceptibility

Variant & Polymorphism

Candidate gene

Marker

Therapy target

ANIMAL & CELL MODELS