Prion protein inhibits microtubule assembly by inducing tubulin oligomerization

Journal Article · Fri Oct 13 04:00:00 EDT 2006 · Biochemical and Biophysical Research Communications

DOI:https://doi.org/10.1016/j.bbrc.2006.08.051· OSTI ID:20854517

Nieznanski, Krzysztof ^[1]; Podlubnaya, Zoya A ^[2]; Nieznanska, Hanna ^[1]

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1. Nencki Institute of Experimental Biology, Department of Muscle Biochemistry, Warsaw (Poland)
2. Institute of Theoretical and Experimental Biophysics, Laboratory of Structure and Function of Muscle Proteins, Pushchino (Russian Federation)

A growing body of evidence points to an association of prion protein (PrP) with microtubular cytoskeleton. Recently, direct binding of PrP to tubulin has also been found. In this work, using standard light scattering measurements, sedimentation experiments, and electron microscopy, we show for First time the effect of a direct interaction between these proteins on tubulin polymerization. We demonstrate that full-length recombinant PrP induces a rapid increase in the turbidity of tubulin diluted below the critical concentration for microtubule assembly. This effect requires magnesium ions and is weakened by NaCl. Moreover, the PrP-induced light scattering structures of tubulin are cold-stable. In preparations of diluted tubulin incubated with PrP, electron microscopy revealed the presence of {approx}50 nm disc-shaped structures not reported so far. These unique tubulin oligomers may form large aggregates. The effect of PrP is more pronounced under the conditions promoting microtubule formation. In these tubulin samples, PrP induces formation of the above oligomers associated with short protofilaments and sheets of protofilaments into aggregates. Noticeably, this is accompanied by a significant reduction of the number and length of microtubules. Hence, we postulate that prion protein may act as an inhibitor of microtubule assembly by inducing formation of stable tubulin oligomers.

• OSTI ID: 20854517
• Journal Information: Biochemical and Biophysical Research Communications, Journal Name: Biochemical and Biophysical Research Communications Journal Issue: 1 Vol. 349; ISSN 0006-291X; ISSN BBRCA9
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
ELECTRON MICROSCOPY
LIGHT SCATTERING
MICROTUBULES
POLYMERIZATION
PROTEINS
SEDIMENTATION
SODIUM CHLORIDES
TURBIDITY