Summary
We describe the production of circles in chromomeric loops during the pachytene stage of the spermatocytes. These circles are found attached to chromatin or already free in the nucleoplasm. Each circle measures an average of 3700 Å in circunference. We suggest that such circles might indicate the presence of tandem repetitions.
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This work was supported by grants from Brazilian National Research Council-CNPq, Fundaçaó de Amparo à Pesquisa do Estado de S. Paulo-FAPESP and Instituto Butantan Research Found-FEDIB.
We are grateful to Dr A. Brunner, Jr, for the permission to use the electron microscope.
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Beçak, M.L., Carneiro, S.M. & Fukuda, K. Circles in spermatocyte chromatin loops. Electron microscopy and AgAs-NORs studies. Experientia 34, 171–173 (1978). https://doi.org/10.1007/BF01944658
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DOI: https://doi.org/10.1007/BF01944658