Fig. 2.
The sgg locus is disrupted in nonhabituating mutants. (A) Two transcriptional splice variants that code for SGG proteins detectable in adults (additional SGG forms are primarily expressed during development) (23). The coding region is shaded. twkr is a p[GawB] transposon inserted at position 8858 of AE104140. sggE6 is a 3,330-base deletion initiating 1,016 bases 5′ to the twkr insertion site, deleting the translation initiation codon of the adult proteins. Ser-9 (S9) is coded by the exon deleted in sggE6. (B) Western blot of adult fly heads, probed with antibodies against SGG kinase domain, S9-containing peptide from human sequence, and α-tubulin. SGG39 and SGG10 are the higher and lower molecular weight bands, respectively. (C) Kinase activity of SGG proteins. Equivalent amounts of control (sggE3) and mutant (sggE6) proteins were immunoprecipitated from fly heads. sggE6 has an 8-fold reduction in levels of SGG protein. Kinase activity was measured on a CREB peptide substrate, and values were normalized to the control after background subtraction. Error bars are standard deviation. P > 0.05 by t test.