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Human autoantibodies reveal titin as a chromosomal protein.

ABSTRACT: Assembly of the higher-order structure of mitotic chromosomes is a prerequisite for proper chromosome condensation, segregation and integrity. Understanding the details of this process has been limited because very few proteins involved in the assembly of chromosome structure have been discovered. Using a human autoimmune scleroderma serum that identifies a chromosomal protein in human cells and Drosophila embryos, we cloned the corresponding Drosophila gene that encodes the homologue of vertebrate titin based on protein size, sequence similarity, developmental expression and subcellular localization. Titin is a giant sarcomeric protein responsible for the elasticity of striated muscle that may also function as a molecular scaffold for myofibrillar assembly. Molecular analysis and immunostaining with antibodies to multiple titin epitopes indicates that the chromosomal and muscle forms of titin may vary in their NH2 termini. The identification of titin as a chromosomal component provides a molecular basis for chromosome structure and elasticity.

SUBMITTER: Machado C

PROVIDER: S-EPMC2148454 | biostudies-literature | 1998 Apr

REPOSITORIES: biostudies-literature

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Human autoantibodies reveal titin as a chromosomal protein.

Machado C C Sunkel C E CE Andrew D J DJ

The Journal of cell biology 19980401 2

Assembly of the higher-order structure of mitotic chromosomes is a prerequisite for proper chromosome condensation, segregation and integrity. Understanding the details of this process has been limited because very few proteins involved in the assembly of chromosome structure have been discovered. Using a human autoimmune scleroderma serum that identifies a chromosomal protein in human cells and Drosophila embryos, we cloned the corresponding Drosophila gene that encodes the homologue of vertebr ...[more]

PMID: 9548712

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Autoantibodies are abundant in all human sera: a demographic characterization via protein microarrays

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