A human-specific gene in microglia.

Bibliographic Collection: 
CARTA-Inspired Publication, APE
Publication Type: Journal Article
Authors: Hayakawa, Toshiyuki; Angata, Takashi; Lewis, Amanda L; Mikkelsen, Tarjei S; Nissi M Varki; Ajit Varki
Year of Publication: 2005
Journal: Science
Volume: 309
Issue: 5741
Pagination: 1693
Date Published: 2005 Sep 9
Publication Language: eng
ISSN: 1095-9203
Keywords: Animals, Biological Evolution, Brain, Exons, Gene Conversion, Humans, Lectins, Membrane Proteins, Microglia, Pan troglodytes, Phylogeny, Pongo pygmaeus, Pseudogenes, Regulatory Sequences, Nucleic Acid, Sialic Acids

Recent studies have shown multiple differences between humans and apes in sialic acid (Sia) biology, including Siglecs (Sia-recognizing-Ig-superfamily lectins). Comparisons with the chimpanzee genome indicate that human SIGLEC11 emerged through human-specific gene conversion by an adjacent pseudogene. Conversion involved 5 cent untranslated sequences and the Sia-recognition domain. This human protein shows reduced binding relative to the ancestral form but recognizes oligosialic acids, which are enriched in the brain. SIGLEC11 is expressed in human but not in chimpanzee brain microglia. Further studies will determine if this event was related to the evolution of Homo.

DOI: 10.1126/science.1114321
Alternate Journal: Science