SPTLC1

Serine palmitoyltransferase, which consists of two different subunits, is the key enzyme in sphingolipid biosynthesis. It converts L-serine and palmitoyl-CoA to 3-oxosphinganine with pyridoxal 5'-phosphate as a cofactor. The product of this gene is the long chain base subunit 1 of serine palmitoyltransferase. Mutations in this gene were identified in patients with hereditary sensory neuropathy type 1. Alternatively spliced variants encoding different isoforms have been identified. [provided by RefSeq]

serine palmitoyltransferase, long chain base subunit 1

Serine palmitoyltransferase (SPT) (PubMed:19416851).
The heterodimer formed with SPTLC2 or SPTLC3 constitutes the catalytic core (PubMed:19416851).
The composition of the serine palmitoyltransferase (SPT) complex determines the substrate preference (PubMed:19416851).
The SPTLC1-SPTLC2-SPTSSA complex shows a strong preference for C16-CoA substrate, while the SPTLC1-SPTLC3-SPTSSA isozyme uses both C14-CoA and C16-CoA as substrates, with a slight preference for C14-CoA (PubMed:19416851).
The SPTLC1-SPTLC2-SPTSSB complex shows a strong preference for C18-CoA substrate, while the SPTLC1-SPTLC3-SPTSSB isozyme displays an ability to use a broader range of acyl-CoAs, without apparent preference (PubMed:19416851).
Required for adipocyte cell viability and metabolic homeostasis (By similarity).

Biological Process ceramide biosynthetic processManual Assertion Based On ExperimentIDA:MGI
Biological Process positive regulation of lipophagyManual Assertion Based On ExperimentIDA:MGI
Biological Process regulation of fat cell apoptotic processISS:UniProtKB
Biological Process sphinganine biosynthetic processIEA:Ensembl
Biological Process sphingolipid biosynthetic processManual Assertion Based On ExperimentIDA:MGI
Biological Process sphingolipid metabolic processManual Assertion Based On ExperimentTAS:ProtInc
Biological Process sphingomyelin biosynthetic processIEA:Ensembl
Biological Process sphingosine biosynthetic processManual Assertion Based On ExperimentIDA:ComplexPortal

Endoplasmic reticulum membrane

Neuropathy, hereditary sensory and autonomic, 1A (HSAN1A):
A form of hereditary sensory and autonomic neuropathy, a genetically and clinically heterogeneous group of disorders characterized by degeneration of dorsal root and autonomic ganglion cells, and by prominent sensory abnormalities with a variable degree of motor and autonomic dysfunction. The neurological phenotype is often complicated by severe infections, osteomyelitis, and amputations. HSAN1A is an autosomal dominant axonal form with onset in the second or third decades. Initial symptoms are loss of pain, touch, heat, and cold sensation over the feet, followed by distal muscle wasting and weakness. Loss of pain sensation leads to chronic skin ulcers and distal amputations.

Lumenal: 1-15
Helical: 16-36
Cytoplasmic: 37-473

Phosphorylation at Tyr-164 inhibits activity and promotes cell survival.