Biomaterial Database

Electron microscopic analysis of the banding pattern in the salivary gland chromosomes of Drosophila melanogaster. Divisions 11 through 20 of X. 1993

A O Saura, and T I Heino, and V Sorsa

Department of Genetics, University of Helsinki, Finland.

The banding pattern of the proximal half of the polytene salivary gland X chromosome of Drosophila melanogaster was studied using thin section electron microscopy. The bands were identified according to Bridges' revised light microscopic map. On Bridges' map, the divisions 11 to 20 contain 112 single bands and as many as 181 double bands. A majority of Bridges' single bands were identified in the thin sections. A total of 23 Bridges' single bands (and 4 bands of division 20) could not be found; in particular, bands were missing from the difficult regions 11DE, 15A, 15C and 16A. Electron microscopy showed the existence of 18 additional faint bands, 4 at the region 18D and 7 at 19EF. Bridges' faintest single bands and the new bands were best seen in formaldehyde fixed material. About 1/4 of Bridges' double bands were found to be made up of two separate bands each. The remaining Bridges' doublets include all kinds of bands: broad, narrow, dark, faint, puffed. Many of them look single in thin sections.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D002871	Chromosome Banding	Staining of bands, or chromosome segments, allowing the precise identification of individual chromosomes or parts of chromosomes. Applications include the determination of chromosome rearrangements in malformation syndromes and cancer, the chemistry of chromosome segments, chromosome changes during evolution, and, in conjunction with cell hybridization studies, chromosome mapping.	Banding, Chromosome,Bandings, Chromosome,Chromosome Bandings
D004331	Drosophila melanogaster	A species of fruit fly frequently used in genetics because of the large size of its chromosomes.	D. melanogaster,Drosophila melanogasters,melanogaster, Drosophila
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
D012469	Salivary Glands	Glands that secrete SALIVA in the MOUTH. There are three pairs of salivary glands (PAROTID GLAND; SUBLINGUAL GLAND; SUBMANDIBULAR GLAND).	Gland, Salivary,Glands, Salivary,Salivary Gland
D014960	X Chromosome	The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in human and other male-heterogametic species.	Chromosome, X,Chromosomes, X,X Chromosomes