I am reading a journal paper about the protein kinase GSK3 and I have come across the following statement:
Although commonly referred to as isoforms, GSK3α and GSK3β are actually paralogs, homologous proteins derived from different genes.
I am not sure what the difference is between an isoform and a paralog. I have Googled both definitions and paralogs refer to 'genes that derive from the same ancestral genes'. Whereas isoforms refer to 'any of two or more functionally similar proteins that have a similar but not identical amino acid sequence and are either encoded by different genes or by RNA transcripts from the same gene which have had different exons removed'
These definitions seem quite similar to me so I was wondering if there are any significant differences between paralogs and isoforms? Any insights are appreciated.