RESUMO
Human leukocyte antigen (HLA) high-resolution matching is routinely performed in the case of hematopoietic stem cell transplantation. Misdiagnosis of rare or new variants will result in additional unknown mismatches that can trigger graft versus host disease and/or graft failure. Using a mono allelic sequencing strategy, we obtained >90% first-step sequence-based high-resolution typing results, conforming to the standards set down by the European Federation for Immunogenetics. During this routine analysis, eight new HLA alleles were identified, including one DRB1*12 null variant, DRB1*12:24N and three other coding mutants, resulting in a change of properties of the corresponding antigens.
Assuntos
Antígenos HLA-DR/genética , Alelos , Sequência de Bases , Bélgica , Cadeias HLA-DRB1 , Teste de Histocompatibilidade , Humanos , Masculino , População Branca/genéticaRESUMO
Xyloglucan endotransglycosylase/hydrolases (XTHs) are enzymes that cleave and rejoin xyloglucan chains. To trace the evolutionary origin of XTHs, we used Selaginella kraussiana, a representative of the most primitive land plants (Lycopodiophyta). A Southern blot with a digoxigenin-labeled probe, designed on the conserved catalytic site of XTHs, indicated nine genes. The presence of at least seven functional XTHs was detected by isoelectric focusing (IEF) followed by overlaying the gel with a XET-test paper. Together, these results indicate that XTHs are encoded by a multi-gene family that originated during or even before the colonization of land by plants.
Assuntos
Glicosiltransferases/genética , Família Multigênica , Proteínas de Plantas/genética , Selaginellaceae/enzimologia , Sequência de Aminoácidos , Southern Blotting , Sequência Conservada , Focalização Isoelétrica , Selaginellaceae/genéticaRESUMO
The endotransglucosylase action of the enzyme xyloglucan endotransglucosylase/hydrolase (XTH) was localized in the roots of diverse vascular plants: club-mosses (lycopodiophytes), ferns, gymnosperms, monocots, and dicots. High action was always found in the epidermis cell wall of the elongation zone and in trichoblasts in the differentiation zone. Clearly XTH and its action in root development evolved before the evolutionary divergence of ferns and seed plants and also of the lycopodiophytes and euphyllophytes.