Transcription factor Sp1 family (IPR030450)

Short name: Sp1_fam

Family relationships


The Sp/Kruppel-like factor (Sp/KLF) super-family of C2H2-type zinc finger-containing transcriptional factor consists of two subfamilies: Sp subfamily has 8 (Sp1-Sp8) members and the KLF subfamily has 15 members [PMID: 10454592, PMID: 10570957, PMID: 12354670]. The Sp subfamily may be further divided into two groups, one represented by Sp1-Sp4 and the other consisting of Sp5-Sp8 proteins; the latter group consists of truncated versions of Sp1 [PMID: 9570130, PMID: 10366853].

The primary sequence and domain organisation of Sp1, Sp3 and Sp4 is highly conserved. In addition to three zinc fingers, each of these proteins possesses two glutamine-rich modules that together make up their transcriptional activation domains (AD). Adjacent to the two ADs is a serine/threonine-rich module that may be targeted for posttranslational modifications. In contrast, Sp2 contains one glutamine-rich AD and an S/T module [PMID: 18664368]. Despite their similarities, they have distinct non-redundant functions in vivo [PMID: 20221402].

This entry represents the Sp1-Sp4 group of glutamine-rich Sp transcription factors.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.