High impact information on rb

• The core 1 beta3-Gal-T sequence has minimal homology with conserved sequences found in previously described beta3-galactosyltransferases, suggesting this enzyme is only distantly related to the known beta3-galactosyltransferase family [1].
• During embryogenesis beta 3 is restricted to and is expressed in all of the developing muscles [2].
• A variant beta-tubulin isoform of Drosophila melanogaster (beta 3) is expressed primarily in tissues of mesodermal origin in embryos and pupae, and is utilized in populations of transient microtubules [2].
• In addition, early in pupal development beta 3 is expressed in the imaginal discs, while at later times beta 3 is expressed in the epidermal cells of the wing blade, the optic lobe, the ovaries, and the testes [2].
• Defective pigment granule biogenesis and aberrant behavior caused by mutations in the Drosophila AP-3beta adaptin gene ruby [3].

Biological context of rb

• The beta 3 tubulin gene expression is also spatially regulated, beta 3 mRNA being restricted to the mesoderm [4].
• The octamer between segments beta 2 and beta 3 that maintains a specific register between true binding sites was found to have an indirect role in interchain binding by stabilizing neighboring segments [5].

Associations of rb with chemical compounds

• Mutation of the human beta3 subunit asparagine to methionine (beta3 N289M found in the equivalent position in Rdl completely inhibited both the GABA-modulatory and GABA-mimetic action of etomidate (10-300 microM) acting at alpha6beta3 N289Mgamma2L receptors [6].

Other interactions of rb

• While the beta 1 tubulin gene is constitutively expressed during development, beta 3 mRNA is restricted to two distinct phases: mid embryogenesis and metamorphosis [4].
• Neither beta 1 nor beta 3 are detectable in the axoneme in the wild-type situation [7].

References