Disease relevance of Fstl1

• A follistatin-like gene, mac25, may act as a growth suppressor of osteosarcoma cells [1].
• Potential preventive effects of follistatin-related protein/TSC-36 on joint destruction and antagonistic modulation of its autoantibodies in rheumatoid arthritis [2].

High impact information on Fstl1

• Ameliorative effects of follistatin-related protein/TSC-36/FSTL1 on joint inflammation in a mouse model of arthritis [3].
• For two candidates, Igfbp4 and Fstl, interdigital limb bud expression was reduced in Hoxa13 mutants [4].
• FRP was first cloned as a transforming growth factor-beta1-inducible protein (called TSC-36) from a mouse osteoblastic cell line and was suggested to have some roles in the negative regulation of cellular growth [5].
• One, tomoregulin, is an integral membrane protein with both EGF- and follistatin-like motifs in its extracellular domain [6].
• As an extracellular regulatory protein, we have identified a novel follistatin-like protein, named follistatin-related gene (FLRG) [7].

Biological context of Fstl1

• Previous studies in chick have identified Fstl1 as a regulator of early mesoderm patterning, somitogenesis, myogenesis and neural development [8].
• A nearly full-length copy of TSC-36 cDNA was isolated, and an open reading frame indicated that it encodes a protein of 35 kDa [9].
• Developmental expression of mouse Follistatin-like 1 (Fstl1): Dynamic regulation during organogenesis of the kidney and lung [8].
• Northern blot analysis showed that the TSC-36 gene expression was certainly upregulated by estrogen [10].
• A cDNA clone was isolated and its nucleotide sequence identified it as TSC 36, previously called follistatin-related polypeptide [10].

Anatomical context of Fstl1

• In the majority of tissues, Fstl1 is strongly expressed in the mesenchymal component and excluded from the epithelium [8].
• Notable exceptions include the central nervous system, in which Fstl1 expression is entirely absent with the exception of the choroid plexi and floor plate, the lung, in which Fstl1 expression can be seen in airway epithelia and the kidney, in which collecting ducts and nascent nephron epithelia express the highest levels of Fstl1 [8].

Associations of Fstl1 with chemical compounds

• These findings indicate that TSC-36 may be one of the estrogen-regulated genes in osteoblastic cells [10].

Other interactions of Fstl1

• TMEFF1 and TMEFF2 are putative transmembrane proteins comprised of one epidermal growth factor (EGF)-like domain and two follistatin-like domains [11].
• (c) SPARC peptides containing follistatin-like and copper-binding sequences were without obvious effect, whereas SPARC peptide 4.2, corresponding to a disulfide-bonded, Ca(2+)-binding domain, was associated with a reduction in axial structures that led eventually to complete ventralization of the embryos [12].

Analytical, diagnostic and therapeutic context of Fstl1

• TSC-36 mRNA level was the highest in the lung among mouse organs, and on in situ hybridization, the TSC-36 transcript was detected in the alveolar epithelium but not in the bronchial epithelium [13].

References