Interfering polysialyltransferase ST8SiaII/STX mRNA inhibits neurite growth during early hippocampal development.
Polysialic acid (PSA) attached to NCAM is involved in cell-cell interactions participating in structural and functional plasticity of neuronal circuits. Two polysialyltransferases, ST8SiaII/STX and ST8SiaIV/PST, polysialylate NCAM. We previously suggested that ST8SiaII/STX is the key enzyme for polysialylation in hippocampus. Here, polysialyltransferase mRNA interference experiments showed that, knock down of ST8SiaIV/PST transcripts did not affect PSA expression, but PSA was almost absent from neuronal surfaces when ST8SiaII/STX mRNA was interfered. Non-polysialylated neurons bore a similar number of neurites per cell than polysialylated neurons. However, non-polysialylated processes were shorter and a lower density of synaptophysin clusters accompanied this reduced neuritic growth. Therefore, ST8SiaII/STX expression is essential to allow a correct neuritic development at initial stages of hippocampus ontogeny.
Brocco
Marcela A
MA
Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús-Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional de General San Martín, Buenos Aires, Argentina. mbrocco@iib.unsam.edu.ar
Frasch
Alberto C C
AC
D000818:Animals; D001483:Base Sequence; D017931:DNA Primers; D006624:Hippocampus / Q000254:growth & development* / Q000378:metabolism; D016501:Neurites; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012799:Sialyltransferases / Q000235:genetics*; D016708:Synaptophysin / Q000378:metabolism
D017931:DNA Primers; D012333:RNA, Messenger; D016708:Synaptophysin; C046778:CMP-N-acetylneuraminate-poly-alpha-2,8-sialosyl sialyltransferase; D012799:Sialyltransferases