The gene encoding SLP-2 was 3250 bp long and consisted of ten exons interrupted by nine introns.

There are 5 transcripts in this gene. However, a single 1.3 kb mRNA transcript encoding SLP-2 was ubiquitously expressed, and the translation length is 356 residues (Owczarek et al., 2001).

No known pseudogenes.

NP_038470; 356 aa.
Human SLP-2 is presented on chromosome 9p13. The sequence at the 5-end of the mRNA is interesting for the presence of three potential ATG initiator sites, all sharing the same open reading frame however, commonly forms a 356 amino acid residue polypeptide with a predicted molecular weight of 38.5 kDa. Similar to other family members, SLP-2 as well as the stomatin from other species shares a characteristic NH2-terminal hydrophobic domain as well as a consensus cognate stomatin signature sequence that defines the stomatin gene family, however, it lacks the NH2-terminal hydrophobic domain (Wang et al., 2000). The SLP-2 protein contains an alanine-rich domain and a number of potential protein kinase C phosphorylation sites, cAMP-and-cGMP-dependent protein kinase phosphorylation sites and casein kinase II phosphorylation sites.

SLP-2 is widely expressed in many tissues and thought as a new component of the peripheral membrane skeleton. Especially, in the erythrocyte membrane, it also appears to exist at least partially as an oligomeric protein complex. The overexpression of SLP-2 can be found in many kinds of human tumors, such as esophageal squamous cell carcinoma, laryngeal squamous cell carcinoma, endometrial adenocarcinoma, and lung cancer.

Predominantly on plasma membrane and in the cytoplasm.

Human SLP-2 protein with unknown function, we hypothesize that SLP-2 may link stomatin or other integral membrane proteins to the peripheral cytoskeleton and thereby play a role in regulating ion channel conductances or the organization of sphingolipid and cholesterol-rich lipid rafts. Some recent results indicated that SLP-2 protein can significantly influence on multi-tumor progression, which allowed us to identify this unwell-known gene that maybe modulate invasion and metastasis of different cancers.

SLP-2 is one of the members of the Stomatin superfamily, among which identified vertebrate homologues are SLP-1, SLP-2, and SLP-3. SLP-1 is most abundant in brain and shares many similarities with UNC-24 (STOML1). SLP-3 is specifically expressed in olfactory sensory neurons (Seidel et al., 1998; Goldstein et al., 2003).

No mutations have been reported for SLP-2. Mutation detection of SLP-2 exons was done using PCR and automated sequencing with 30 patient-matched human esophageal cancer tissues. No mutation was found within the open-reading frame of SLP-2 after sequencing results were aligned by the procedure SeqMan of DNAStar software (Zhang et al., 2006).