Abstract
BackgroundNeuronal migration involves the directional migration of immature neurons. During much of the migration period these neurons are polarized with defined leading and trailing processes. Stk25 has been shown to bind to the LKB1 activator STRAD and regulate neuronal polarization and dendritogenesis in an opposing manner to Reelin-Dab1 signaling. It is not known, however, whether Stk25 controls neuronal migration, a key developmental process regulated by Reelin-Dab1 signal transduction.FindingsHere we find that while constitutive Stk25 deficiency does not lead to neuronal phenotypes, acute reduction by either Cre-mediated gene inactivation or by knockdown causes a developmental neuronal migration error. Furthermore, we find that knockdown of LKB1, STRAD and GM130, molecules that have previously been implicated with Stk25, causes similar aberrations in neuronal migration.ConclusionsLoss of Stk25 function early in development likely leads to functional compensation for its roles in neuronal development. Stk25 regulates neuronal positioning, possibly as part of the LKB1-STRAD-Stk25-GM130 pathway that was previously shown to be important for neuronal polarization.
Highlights
MethodsGeneration of the Stk floxed and knockout mice Exons 4 and 5 of the Stk gene were floxed and a PGK-EM7 neomycin cassette flanked by Frt sites was introduced into intron 5 by recombineering a BAC to generate the knockout vector (Figure 1A)
Neuronal migration involves the directional migration of immature neurons
Stk25 regulates neuronal positioning, possibly as part of the LKB1-STRAD-Stk25-GM130 pathway that was previously shown to be important for neuronal polarization
Summary
Generation of the Stk floxed and knockout mice Exons 4 and 5 of the Stk gene were floxed and a PGK-EM7 neomycin cassette flanked by Frt sites was introduced into intron 5 by recombineering a BAC to generate the knockout vector (Figure 1A). The vector was electroporated into C57BL/6-129/Sv hybrid ES cells at the University of Connecticut transgenic core (Farmington CT, USA). The PGK-EM7 neomycin resistance cassette was removed by breeding the chimeric founder mice with Flp-expressing transgenic mice leaving sole Frt and loxP sites in the intron after recombination (Figure 1A). The Flp transgene was outbred by backcrossing with wild-type C57BL/6 mice. The resultant animals are referred to here as heterozygous or homozygous floxed Stk (Stk25fl/+ or Stk25fl/fl, respectively) mice. Cre-mediated excision of exons 4 and 5 is predicted to cause the frameshift-termination of translation in exon 6 after translating 87 residues of the Stk Nterminus (Figure 1A)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
