The two macronuclear histone H4 genes of the hypotrichous ciliate Stylonychia lemnae
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Updated: Oct 24, 2026

Expression Analysis of Mammalian Linker-histone Subtypes
Published on: March 19, 2012
1Medizinisch-Naturwissenschaftliches-Forschungszentrum, Universität Tuebingen, FRG.
Abstract:
Macronuclear DNA of hypotrichous ciliates is organized in short gene-sized molecules, each containing all regulatory sequences for autonomous replication and expression. In these organisms the histone genes are not clustered but dispersed on different molecules of various sizes. Two histone H4 genes containing fragments, one of 1.7 kb and one of 2.8 kb, were found in the macronucleus of Stylonychia lemnae. Restriction and sequence data reveal that the two genes-sized pieces are derived from different micronuclear precursors. Both histone H4 genes code for the same protein of 103 aminoacids but differ greatly in their 5'-and 3'-regions.
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