ASPH

This gene is thought to play an important role in calcium homeostasis. The gene is expressed from two promoters and undergoes extensive alternative splicing. The encoded set of proteins share varying amounts of overlap near their N-termini but have substantial variations in their C-terminal domains resulting in distinct functional properties. The longest isoforms (a and f) include a C-terminal Aspartyl/Asparaginyl beta-hydroxylase domain that hydroxylates aspartic acid or asparagine residues in the epidermal growth factor (EGF)-like domains of some proteins, including protein C, coagulation factors VII, IX, and X, and the complement factors C1R and C1S. Other isoforms differ primarily in the C-terminal sequence and lack the hydroxylase domain, and some have been localized to the endoplasmic and sarcoplasmic reticulum. Some of these isoforms are found in complexes with calsequestrin, triadin, and the ryanodine receptor, and have been shown to regulate calcium release from the sarcoplasmic reticulum. Some isoforms have been implicated in metastasis. [provided by RefSeq]

aspartate beta-hydroxylase

Isoform 1: specifically hydroxylates an Asp or Asn residue in certain epidermal growth factor-like (EGF) domains of a number of proteins.
Isoform 8: membrane-bound Ca2+-sensing protein, which is a structural component of the ER-plasma membrane junctions. Isoform 8 regulates the activity of Ca(+2) released-activated Ca(+2) (CRAC) channels in T-cells.

Activation of cysteine-type endopeptidase activity Source: BHF-UCL
Activation of store-operated calcium channel activity Source: UniProtKB
Calcium ion homeostasis Source: UniProtKB
Calcium ion transmembrane transport Source: UniProtKB
Cellular response to calcium ion Source: UniProtKB
Detection of calcium ion Source: BHF-UCL
Ion transmembrane transport Source: Reactome
Muscle contraction Source: ProtInc
Peptidyl-aspartic acid hydroxylation Source: GO_Central
Positive regulation of calcium ion transport into cytosol Source: UniProtKB
Positive regulation of intracellular protein transport Source: UniProtKB
Positive regulation of proteolysis Source: BHF-UCL
Positive regulation of ryanodine-sensitive calcium-release channel activity Source: BHF-UCL
Positive regulation of transcription, DNA-templated Source: UniProtKB
Regulation of cardiac conduction Source: Reactome
Regulation of cardiac muscle contraction by regulation of the release of sequestered calcium ion Source: BHF-UCL
Regulation of cell communication by electrical coupling Source: BHF-UCL
Regulation of inositol 1,4,5-trisphosphate-sensitive calcium-release channel activity Source: UniProtKB
Regulation of release of sequestered calcium ion into cytosol by sarcoplasmic reticulum Source: BHF-UCL
Regulation of ryanodine-sensitive calcium-release channel activity Source: BHF-UCL
Response to ATP Source: UniProtKB

Isoform 1: Endoplasmic reticulum membrane
Isoform 4: Sarcoplasmic reticulum membrane
Isoform 8: Endoplasmic reticulum membrane

Facial dysmorphism, lens dislocation, anterior segment abnormalities, and spontaneous filtering blebs (FDLAB): A syndrome characterized by dislocated crystalline lenses and anterior segment abnormalities in association with a distinctive facies involving flat cheeks and a beaked nose. Some affected individuals develop highly unusual non-traumatic conjunctival cysts (filtering blebs).

Cytoplasmic: 1-53 aa
Helical: 54-74 aa
Lumenal: 75-758 aa