Proceedings of the American Academy of Arts and Sciences.

v. 35 (1899-1900)

Mutations at Phosphorylation Sites of Xenopus Microtubule-associated Protein 4 Affect Its Microtubule-binding Ability and Chromosome Movement during Mitosis

Microtubule-associated proteins (MAPs) bind to and stabilize microtubules (MTs) both in vitro and in vivo and are thought to regulate MT dynamics during the cell cycle. It is known that p220, a major MAP of Xenopus, is phosphorylated by p34cdc2 kinase as well as MAP kinase in mitotic cells, and that the phosphorylated p220 loses its MT-binding and -stabilizing abilities in vitro. We cloned a full-length cDNA encoding p220, which identified p220 as a Xenopus homologue of MAP4 (XMAP4). To examine the physiological relevance of XMAP4 phosphorylation in vivo, Xenopus A6 cells were transfected with cDNAs encoding wild-type or various XMAP4 mutants fused with a green fluorescent protein. Mutations of serine and threonine residues at p34cdc2 kinase-specific phosphorylation sites to alanine interfered with mitosis-associated reduction in MT affinity of XMAP4, and their overexpression affected chromosome movement during anaphase A. These findings indicated that phosphorylation of XMAP4 (probably by p34cdc2 kinase) is responsible for the decrease in its MT-binding and -stabilizing abilities during mitosis, which are important for chromosome movement during anaphase A.

Proceedings of the American Academy of Arts and Sciences.

v. 57 (1921-1922)

Transactions of the Wisconsin Academy of Sciences, Arts, and Letters.

13

Proceedings of the American Academy of Arts and Sciences.

v. 37 (1901-1902)

Memorial to the Academy of Arts and Sciences, 1826 April

Four drafts of a letters requesting support to reprint Croswell's 1791 Tables for Computing the Longitude by the Lunar Observations, with two related documents.

Memorial to the Academy of Arts and Sciences, 1828 April

Five drafts of a letters requesting support to reprint Croswell's 1791 Tables for Computing the Longitude by the Lunar Observations.

Proceedings of the American Academy of Arts and Sciences.

v. 52 (1916-1917)

Proceedings of the American Academy of Arts and Sciences.

v. 2 (1848-1852)