Differences in the regulation of microtubule stability by the pro‐rich region variants of microtubule‐associated protein 4

Abstract

We have recently reported a neural variant of microtubule-associated protein 4 with a short pro-rich region (MAP4-SP). Here, we show that the neural MAP4 has reduced microtubule-stabilizing activity, compared to the ubiquitous MAP4 with a long pro-rich region (MAP4-LP), both in vitro and in vivo. Fluorescence recovery after photobleaching analyses revealed that the interaction of MAP4-SP with the microtubules is very rapid, with a half-time of fluorescence recovery of 7±2.36s, compared to 19.5±3.03s in case of MAP4-LP. The dynamic interaction of MAP4-SP with microtubules in neural cells may contribute to the dynamic behaviors of extending neurites