Sciencemadness Discussion Board

Need help identifying 2 proteins in a research paper, cannot find them in protein databases

RJR - 16-1-2021 at 20:12

The first one identified is FST 291. FST 288 is apparently a known protein with lots of literature https://www.ebi.ac.uk/pdbe/entry/pdb/5jhw/protein/2
But I couldn't find any mention of FST 291

The other one is FST-315. I found an isoform of human follistatin, which has 317 AAs which is close but not quite a match. I also found an activin-follistatin complex with 315 AAs, but I'm not sure if that's a match https://www.ncbi.nlm.nih.gov/protein/2P6A_C


Here's the figure with the proteins (in part a)


Thanks in advance!

zinc finger - 5-5-2021 at 04:07

So this seems to be the paper you are referring to? https://www.nature.com/articles/s41598-019-47818-w

Here you can find the structural and sequence data for follistatin 315: https://www.rcsb.org/sequence/2P6A
You can verify that it is indeed the same Protein by comparing the annotated features lengths.


The question about the follistatin 291 is more difficult. As I understand it they assigned the name FST291 to the remining rest of FST315 after removing the CD. When searching for ACE-083 you get much more results. So I would assume, that it is just the sequence of FST315 until the 291th aa.
"ACE-083 differs from native FST315 by nearly complete removal of the C-terminal domain (CD) and by attachment to
an immunoglobulin Fc domain, which results in dimerization of the follistatin polypeptide."
(Follistatin-based ligand trap ACE083 induces localized hypertrophy
of skeletal muscle with functional
improvement in models of
neuromuscular disease
R. S. Pearsall)

Metacelsus - 6-5-2021 at 14:37

Quote: Originally posted by zinc finger  
So I would assume, that it is just the sequence of FST315 until the 291th aa.
"ACE-083 differs from native FST315 by nearly complete removal of the C-terminal domain (CD) and by attachment to
an immunoglobulin Fc domain, which results in dimerization of the follistatin polypeptide."


Yes, this is correct. FST291 likely does not occur naturally, which is why it's not in databases.