title: In situ comparative studies on subnucleolar distribution and configuration of plant rDNA.
abstract: The distribution and configurations of nucleolar DNA in Pisum sativum L., Allium sativum L., Triticum aestivum L. were analyzed by specific cytochemical staining using NAMA-Ur. It has been observed that in the nucleoli of different plant species, the DNA occupied different positions in different areas, which may imply a different status and strategy of rDNA transcription. Our results showed irregular clumps of rDNA surrounding FCs in semi-circular formations in P. sativum and T. aestivum, indicating a regular pattern of rDNA distribution and supporting the helix model of rDNA configuration. The rDNA was condensed in some regions and uncondensed in others. Nucleolus-associated chromatin extended from outside the nucleolus to the periphery of the FCs via nucleolar channels, which suggests a possible origin for nucleolar DNA.
authors.affiliation: College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Long
authors.forename: Jie
authors.initials: J
authors.lastname: He
authors.forename: Haijing
authors.initials: H
authors.lastname: Sun
authors.forename: Shui
authors.initials: S
authors.lastname: Hao
authors.forename: Mingda
authors.initials: M
authors.lastname: Jiao
mesh_terms: D002466:Cell Nucleolus / Q000737:chemistry* / Q000648:ultrastructure; D018744:DNA, Plant / Q000032:analysis*; D004275:DNA, Ribosomal / Q000032:analysis*; D005737:Garlic / Q000235:genetics / Q000648:ultrastructure; D018532:Pisum sativum / Q000235:genetics / Q000648:ultrastructure; D014908:Triticum / Q000235:genetics / Q000648:ultrastructure
chemical_list: D018744:DNA, Plant; D004275:DNA, Ribosomal