FSTL1 Human, HEK

FSTL1 comprises several domains, including a secretion signal, a follistatin-like domain, a Kazal-like domain, two EF-hand domains, and a von Willebrand factor type C domain . The human FSTL1 protein sequence shows a high degree of similarity with its mouse counterpart, particularly in the regions beyond the secretion signal .

FSTL1 is involved in multiple biological processes and signaling pathways. It plays a significant role in cardiovascular development and disease, cancer progression, and rheumatoid arthritis . The protein is known for its cardioprotective properties, although the exact mechanisms remain elusive . FSTL1 is also involved in vascularization and immune response regulation .

The biological activity of FSTL1 is influenced by its glycosylation state, which varies between species and tissues . In cardiomyocytes, the glycosylated form promotes proliferation, while the non-glycosylated form has anti-apoptotic properties . Additionally, FSTL1 undergoes extensive post-transcriptional regulation, including the encoding of a microRNA (miR-198) in primates .

FSTL1 has been studied extensively for its role in cardiovascular diseases (CVDs). It is highly expressed in the heart and released into the serum after cardiac injury . Animal studies have shown that FSTL1 has protective effects in various models of heart disease, including inhibiting inflammation, preventing remodeling and fibrosis, and promoting angiogenesis and hypertrophy . Due to its significant role in CVDs, FSTL1 is being explored as a potential biomarker and therapeutic target .

Human recombinant FSTL1 produced in HEK293 cells is a single, glycosylated polypeptide chain containing 296 amino acids, including an 8 amino acid C-terminal His tag . This recombinant form is used in various research applications to study the protein’s functions and potential therapeutic uses.