Aspergillus nidulans Dis1/XMAP215 protein AlpA localizes to spindle pole bodies and microtubule plus ends and contributes to growth directionality.

The dynamics of cytoplasmic microtubules (MTs) is largely controlled by a protein complex at the MT plus end. In Schizosaccharomyces pombe and in filamentous fungi, MT plus end-associated proteins also determine growth directionality. We have characterized the Dis1/XMAP215 family protein AlpA from Aspergillus nidulans and show that it determines MT dynamics as well as hyphal morphology.

The role of the kinesin motor KipA in microtubule organization and polarized growth of Aspergillus nidulans.

Polarized growth in filamentous fungi requires the integrity of the microtubule (MT) cytoskeleton. We found that growing MTs in Aspergillus nidulans merge at the center of fast growing tips and discovered that a kinesin motor protein, KipA, related to Tea2p of Schizosaccharomyces pombe, is required for this process. In a DeltakipA strain, MT plus ends reach the tip but show continuous lateral movement.