TY - JOUR
T1 - A molecular trap inside microtubules probes luminal access by soluble proteins
AU - Nihongaki, Yuta
AU - Matsubayashi, Hideaki T.
AU - Inoue, Takanari
N1 - Publisher Copyright:
© 2021, The Author(s), under exclusive licence to Springer Nature America, Inc.
PY - 2021/8
Y1 - 2021/8
N2 - The uniquely hollow structure of microtubules (MTs) confers characteristic mechanical and biological properties. Although most regulatory processes take place at the outer surface, molecular events inside MTs, such as α-tubulin acetylation, also play a critical role. However, how regulatory proteins reach the site of action remains obscure. To assess luminal accessibility, we first identified luminally positioned residues of β-tubulin that can be fused to a protein of interest. We then developed a chemically inducible technique with which cytosolic proteins can be rapidly trapped at the lumen of intact MTs in cells. A luminal trapping assay revealed that soluble proteins of moderate size can enter the lumen via diffusion through openings at the MT ends and sides. Additionally, proteins forming a complex with tubulins can be incorporated to the lumen through the plus ends. Our approach may not only illuminate this understudied territory, but may also help understand its roles in MT-mediated functions. [Figure not available: see fulltext.].
AB - The uniquely hollow structure of microtubules (MTs) confers characteristic mechanical and biological properties. Although most regulatory processes take place at the outer surface, molecular events inside MTs, such as α-tubulin acetylation, also play a critical role. However, how regulatory proteins reach the site of action remains obscure. To assess luminal accessibility, we first identified luminally positioned residues of β-tubulin that can be fused to a protein of interest. We then developed a chemically inducible technique with which cytosolic proteins can be rapidly trapped at the lumen of intact MTs in cells. A luminal trapping assay revealed that soluble proteins of moderate size can enter the lumen via diffusion through openings at the MT ends and sides. Additionally, proteins forming a complex with tubulins can be incorporated to the lumen through the plus ends. Our approach may not only illuminate this understudied territory, but may also help understand its roles in MT-mediated functions. [Figure not available: see fulltext.].
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U2 - 10.1038/s41589-021-00791-w
DO - 10.1038/s41589-021-00791-w
M3 - Article
C2 - 33941924
AN - SCOPUS:85105281441
SN - 1552-4450
VL - 17
SP - 888
EP - 895
JO - Nature chemical biology
JF - Nature chemical biology
IS - 8
ER -