PAPSS2
Function
Bifunctional enzyme with both ATP sulfurylase and APS kinase activity, which mediates two steps in the sulfate activation pathway. The first step is the transfer of a sulfate group to ATP to yield adenosine 5'-phosphosulfate (APS), and the second step is the transfer of a phosphate group from ATP to APS yielding 3'-phosphoadenylylsulfate/PAPS, the activated sulfate donor used by sulfotransferases (PubMed:11773860, PubMed:19474428, PubMed:23824674, PubMed:25594860). In mammals, PAPS is the sole source of sulfate while APS appears to only be an intermediate in the sulfate-activation pathway (PubMed:11773860, PubMed:19474428, PubMed:23824674, PubMed:25594860). Plays indirectly an important role in skeletogenesis during postnatal growth (PubMed:9771708).
Involvement in disease
Brachyolmia type 4 with mild epiphyseal and metaphyseal changes
BCYM4
A form of brachyolmia, a clinically and genetically heterogeneous skeletal dysplasia primarily affecting the spine and characterized by a short trunk, short stature, and platyspondyly. BCYM4 is an autosomal recessive form with mild epiphyseal and metaphyseal changes. Clinical features include short stature evidenced at birth, short and bowed lower limbs, mild brachydactyly, kyphoscoliosis, abnormal gait, enlarged knee joints. Some BCYM4 patients may manifest premature pubarche and hyperandrogenism associated with skeletal dysplasia and short stature.
None
The disease is caused by variants affecting the gene represented in this entry.
Pathway
Sulfur metabolism; sulfate assimilation.
Sequence Similarities
In the N-terminal section; belongs to the APS kinase family.
In the C-terminal section; belongs to the sulfate adenylyltransferase family.
Tissue Specificity
Expressed in cartilage and adrenal gland.
Alternative names
ATPSK2, PAPSS2, Bifunctional 3'-phosphoadenosine 5'-phosphosulfate synthase 2, PAPS synthase 2, PAPSS 2, Sulfurylase kinase 2, SK 2, SK2