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W E Kalisch

Publications and source records attributed to W E Kalisch.

At least 19 recordsLinked to original sources
PubMed1991

Electron microscopic band-interband pattern of polytene chromosomes in Drosophila nasuta albomicans. 2. Salivary gland chromosome 2L.

The band-interband pattern (division 28-52) of salivary gland chromosome 2L in Drosophila nasuta albomicans was studied by light (LM) and electron microscopy (EM) using squash preparations and surface-spread polytene (SSP) chromosome preparations, respectively. LM and EM maps were complied. Based on the digitized EM patterns of five homologous SSP chromosomes a computerized EM chromosome map was plotted. The EM pattern analysis showed a total number of 479 chromosome bands with an almost 83% increase compared with the LM analysis of squash preparations. By extrapolation of the data from 39% of the polytene genome analysed so far in D. n. albomicans, a total number of 2,926 chromosome bands was calculated. This is almost the same number of bands as was calculated earlier for Drosophila hydei using the same SSP chromosome preparation technique. The data in the literature concerning variations in the number of chromosome bands in different Drosophila species, the various chromosome preparation techniques adopted, and the different criteria used for the EM pattern analyses, are discussed.

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PubMed1991

Electron microscopic band-interband pattern of polytene chromosomes in Drosophila nasuta albomicans. 1. Salivary gland chromosome 2R.

The band-interband pattern of salivary gland chromosome 2R in Drosophila nasuta albomicans (division 53-83) was studied by light (LM) and electron microscopy (EM) using squash preparations and surface-spread polytene (SSP) chromosome preparations, respectively. LM and EM maps were compiled. Based on the digitized EM patterns of five homologous SSP chromosomes a computerized chromosome map was plotted. The EM pattern analysis showed a total number of 662 chromosome bands with an almost 98% increase compared with the LM analysis of squash preparations. The majority (about 92%) of interband lengths in SSP chromosome 2R ranged between 0.25 and 0.64 microns, which equal about 0.8-2.1 kb of totally extended DNA or 2.5-6.4 kb of DNA, if a DNA packing ratio of 0.1 microns/kb is assumed for the interbands of SSP chromosomes.

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PubMed1989

Comparative analysis of glue proteins in the Drosophila nasuta subgroup.

The patterns of protein fractions from total salivary glands and from glue plugs were compared in seven members of the Drosophila nasuta subgroup by the use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The glue protein patterns are member specific concerning the numbers and the electrophoretic mobilities of major and minor glue protein fractions. However, the major fractions of all subgroup members could be grouped into five SDS-PAGE domains according to the homologies of their electrophoretic mobilities, prominence of Coomassie blue staining, and PAS reaction. In all subgroup members, major fractions are involved in posttranslational modifications into larger protein molecules of the final glue. Quantitative estimations of the glue proteins in D. n. nasuta and D. n. albomicans reveal that they constitute between 55 and 60% of the total salivary gland proteins, whereas in D. melanogaster and in D. hydei the fraction is only 32 and 35%, respectively.

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PubMed1988

Glue proteins in Drosophila nasuta.

Larval glue protein fractions of Drosophila nasuta nasuta were analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Seven major and at least four minor glue protein fractions were recognized. Six of the major fractions are glycosylated. They migrate as three prominent doublets (greater than 100, 43, and 30/28 kd). The synthesis of traceable amounts of these major fractions begins already during the second as well as during the early stages of the third larval instar. The 43-kd and the 30/28-kd fractions are coded by X-chromosomal genes. They are probably clustered within the huge puff of division 10, which is the most prominent X-chromosomal puff in the polytene chromosomes of the third larval instar. Complex posttranslational modification of all but one major glue protein fraction (14 kd) leads to the formation of about 15 different protein fractions in the final glue product. The amount of glue protein produced by D. n. nasuta larvae (in relation to the total saliva proteins) is nearly twice the amount produced by D. melanogaster larvae (ca. 55 and 32%, respectively).

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PubMed1985

Laser scanning microscopy of surface spread polytene chromosomes.

A new type of a Laser Scan Microscope (Zeiss) was used for the analysis of the band-interband pattern of polytene chromosomes in Chironomus. In contrast to the previously used techniques of transmission light and electron microscopy, we used differential interference contrast (DIC) in incident light to depict the pattern. Instead of using common squash preparations, we carried out this investigation with surface spread polytene (SSP) chromosome preparations of salivary glands. The combination of techniques used enabled a more detailed light microscopic presentation of polytene structures in individual preparations than conventional techniques used so far for chromosome mapping.

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PubMed1984

Computerized EM maps of surface spread polytene chromosomes 1 digitizing and plotting of banding patterns.

A standard plotting program for the band-interband pattern of polytene chromosome maps was written in EXTENDED BASIC for a pocket computer coupled to a plotter (Sharp PC-1500 + CE-150). In this program, the individual polytene structure (i.e. one chromosome band and its right-handed interband) was digitized using a set of variables: [A] band diameter, [B] band type (solid, dotted, straight or curved bands), [C] band thickness, [D] interband length, [E] interband as well as puff and Balbiani ring outlines, [R] radius (for curved bands), [W] sectioning (of the pattern in chromosome maps) and [V$] reference numbers. The general use of this technique was tested by digitizing and computerized plotting of data from hand-drawn chromosome maps in Chironomus and Drosophila. Electron micrographs of surface spread polytene (SSP) chromosomes from the salivary glands of Chironomus thummi larvae were used to digitize the pattern of region F1-4 in chromosome I. The computerized EM map of this region was compared with the LM map from chromosome squash preparations.

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PubMed1980

DNA replication of a polytene chromosome section in Drosophila prior to and during puffing.

Polytene chromosome sections 63E1-6 of 3L in Drosophila melanogaster were studied by 3H-uridine and 3H-thymidine autoradiography in late third instar larvae and prepupae. In late third instar larvae 63E does not incorporate 3H-uridine. In prepupae, however, a large puff is formed in 63E which is most active in RNA synthesis. 3h-thymidine labeling patterns and frequencies of regions 61A-64C were analysed and the nonpuffed and puffed 63E sections were compared with reference sections. Both in late third instar larvae and in prepupae 63E shows late replication behavior. It is concluded that the decondensation of chromosome bands does not necessarily entail earlier and/or faster DNA replication.

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PubMed1976

Correspondence of banding patterns to 3h-thymidine labeling patterns in polytene chromosomes.

3H-thymidine labeling frequencies over X chromosomal region 1A-4E of Drosophila melanogaster, were analysed with reference to chromosome sections with and without prominent bands. A correspondence was found between band sections and late start of silver grain labeling at the initial stage in combination with late labeling at the end stage of replication. A complementary situation is always to be found over puff/interband sections, where an early start of labeling at the initial stage is generally combined with early labeling completion at the end stage of replication.

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