Biomaterial Database

[Nuclear reconstitution around purified HeLa chromosomes in a cell-free system from Xenopus eggs]. 1994

C M Zhang, and J Qu, and Z H Zhai

Department of Biology, Peking University, Beijing.

Activated Xenopus egg extracts are capable of reconstituting nucleus around the added DNA or chromatin. To understand better the nuclear reconstitution process and the structure of the assembled nucleus, we have developed a cell-free system using activated Xenopus egg extracts and metaphase chromosomes of HeLa cells. We demonstrate that the extracts are efficient promoting the decondensation of the metaphase chromosomes and the nuclear reconstitution around the chromosomes, and that the nuclear reconstitution is a precise process. The reassembled nucleus possesses a typical nuclear envelope, pore complexes, nuclear lamina, nuclear matrix, chromatin, etc., as shown by electron microscopy, embedment and embedment-free electron microscopy, and immunofluorescence method. We also found that the annulate lamellae directly take part in nuclear envelope and pore complex reconstitution by fusing with the double membrane, having reassembled on the surface of chromatin/chromosomes.

UI	MeSH Term	Description	Entries
D008677	Metaphase	The phase of cell nucleus division following PROMETAPHASE, in which the CHROMOSOMES line up across the equatorial plane of the SPINDLE APPARATUS prior to separation.
D010063	Ovum	A mature haploid female germ cell extruded from the OVARY at OVULATION.	Egg,Egg, Unfertilized,Ova,Eggs, Unfertilized,Unfertilized Egg,Unfertilized Eggs
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D002474	Cell-Free System	A fractionated cell extract that maintains a biological function. A subcellular fraction isolated by ultracentrifugation or other separation techniques must first be isolated so that a process can be studied free from all of the complex side reactions that occur in a cell. The cell-free system is therefore widely used in cell biology. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p166)	Cellfree System,Cell Free System,Cell-Free Systems,Cellfree Systems,System, Cell-Free,System, Cellfree,Systems, Cell-Free,Systems, Cellfree
D002875	Chromosomes	In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Chromosome
D005260	Female		Females
D006367	HeLa Cells	The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for, among other things, VIRUS CULTIVATION and PRECLINICAL DRUG EVALUATION assays.	Cell, HeLa,Cells, HeLa,HeLa Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014020	Tissue Extracts	Preparations made from animal tissues or organs (ANIMAL STRUCTURES). They usually contain many components, any one of which may be pharmacologically or physiologically active. Tissue extracts may contain specific, but uncharacterized factors or proteins with specific actions.	Extracts, Tissue