Molecular evolution and in vitro characterization of Botryllus histocompatibility factor

Area of Science:

• Marine biology
• Immunology
• Genetics

Background:

• Botryllus schlosseri colonies fuse by sharing fuhc locus alleles.
• Incompatibility leads to inflammatory responses and melanin scar formation.
• The molecular basis of allorecognition in B. schlosseri is not fully understood.

Purpose of the Study:

• To characterize the Botryllus histocompatibility factor (bhf), a candidate allodeterminant.
• To investigate the polymorphism, isoforms, expression, and localization of bhf.
• To hypothesize the function of bhf in allorecognition.

Main Methods:

• DNA and protein analysis of bhf.
• mRNA-Seq and EST assembly for isoform identification.
• Whole-mount fluorescent in situ hybridization.
• HEK293T cell transfection for protein localization studies.

Main Results:

• Bhf exhibits low polymorphism and lacks typical selection patterns.
• A truncated bhf isoform lacking exon 3 was identified.
• Bhf is co-expressed with cfuhc(sec) in a subset of cells.
• BHF localizes to the cytoplasm and nucleus in HEK293T cells.

Conclusions:

• Bhf's low polymorphism and localization suggest it may not be a direct allorecognition determinant.
• Bhf might function as a scaffolding protein within a larger complex.
• Further research is needed to elucidate bhf's precise role in B. schlosseri allorecognition.