Characteristics of the thirty-two proteotypic peptides for Homo sapiens G3m and IGHG3 alleles.

The proteotypic peptides correspond to an enzymatic AspN and trypsin digestion of the constant region of the IG gamma3 chains encoded by the Homo sapiens IGHG3 gene.aPartial.bUnusual G3m allele [8], [12]. This corresponds to the IGHG3*08 allele. Allotypes G3m10, G3m11 and G3m13 are not expressed owing to the presence of CH3 Asn N44, instead of the CH3 Ser S44 usually present in the other G3m5* alleles [8].cThe IGHG3*11 and IGHG3*12 alleles differ by the number of hinge exons, 4 and 3, respectively (IMGT Repertoire, Gene table http://www.imgt.org) [8], [18].dExpression of the allotype G3m15 is dependent, in addition to CH3 Met M39, on the presence of CH3 His H115 and Tyr Y116 [8].eExpression of the allotype G3m13 is dependent, in addition to CH3 Gln Q98, on the presence of CH3 Ser 44 [8].fExpression of the allotype G3m10 is dependent, in addition to CH3 Ile I101, on the presence of CH3 Ser 44 [8].gExpression of the allotype G3m15 is dependent, in addition to CH3 His H115 and Tyr Y116, on the presence of CH3 Met M39 [8].hExpression of the allotype G3m14 is dependent, in addition to CH3 Arg R115 and Phe F116, on the presence of CH3 Met M84 [8].iExpression of the allotype G3m6 is dependent, in addition to CH3 Glu E98, on the presence of CH3 Ser S44 [8].jExpression of the allotype G3m24 is dependent, in addition to CH3 Val V101, on the presence of CH3 Ser S44 [8].Amino acids in bold are implicated in the discrimination between IGHG3 alleles. “.” : site of enzymatic cut.Amino acids characteristic of the G3m allotypes and IGHG3 alleles are from reference [8]. They are illustrated in the ‘IMGT G3m allele butterfly’ representation [8]. Amino acid sequences are available in the IMGT Repertoire (http://www.imgt.org), IMGT/DomainDisplay and IMGT/GENE-DB [18]. Positions in the CH domains are according to the IMGT unique numbering for C domain [21].