The RNA-binding protein MARTA2 regulates dendritic targeting of MAP2 mRNAs in rat neurons

作者：Zivraj Krishna H; Rehbein Monika; Oelschlaeger Schuett Janin; Schob Claudia; Falley Katrin; Buck Friedrich; Schweizer Michaela; Schepis Antonino; Kremmer Elisabeth; Richter Dietmar; Kreienkamp Hans Juergen; Kindler Stefan^*

来源：Journal of Neurochemistry, 2013, 124(5): 670-684.

DOI：10.1111/jnc.12079

• kinesin
• microtubule
• molecular motor
• ribonucleoprotein particle
• RNA transport
• trans-acting factor

Dendritic targeting of mRNAs encoding the microtubule-associated protein 2 (MAP2) in neurons involves a cis-acting dendritic targeting element. Two rat brain proteins, MAP2-RNA trans-acting protein (MARTA)1 and MARTA2, bind to the cis-element with both high affinity and specificity. In this study, affinity-purified MARTA2 was identified as orthologue of human far-upstream element binding protein 3. In neurons, it resides in somatodendritic granules and dendritic spines and associates with MAP2 mRNAs. Expression of a dominant-negative variant of MARTA2 disrupts dendritic targeting of endogenous MAP2 mRNAs, while not noticeably altering the level and subcellular distribution of polyadenylated mRNAs as a whole. Finally, MAP2 transcripts associate with the microtubule-based motor KIF5 and inhibition of KIF5, but not cytoplasmic dynein function disrupts extrasomatic trafficking of MAP2 mRNA granules. Thus, in neurons MARTA2 appears to represent a key trans-acting factor involved in KIF5-mediated dendritic targeting of MAP2 mRNAs.

• 出版日期2013-3