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As a polyalanine block could be regarded as a sort of
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however, about 13 and variation was small (Fig. 6), sug-
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Though amino acid sequence uniformity of respective
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with multiple motifs infers that the rearrangement rate is
effectively large relative to the magnitude of negative
natural selection. As another possible explanation, varia-
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Acknowledgments. We thank Dr. S. Hayasaka for the A. pernyi
samples. We also appreciate two anonymous reviewers for helpful
comments. We thank Dr. M.G. Goldsmith for a critical reading of the
manuscript. This work was supported by the Enhancement of Center of
Excellence, Special Coordination Funds for Promoting Science and
Technology, Science and Technology Agency, Japan.
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