MeSH note : a Pu.! family member that is expressed primarily in B cells; required for B cell activation
and germinal center formation; found in various animals; identified in Raja eglanteria
in this paper; used to be known as Spi-B protein, an appellation now used for a different
PU.1 family member; amino acid sequence in first source; this record created for Xenopus
Spi-D;