MODULATION OF PROTEIN LEVELS IN CHROMOSOMAL DOSAGE SERIES OF MAIZE: THE BIOCHEMICAL BASIS OF ANEUPLOID SYNDROMES

ABSTRACT Genetically defined dosage series of chromosome arms 1L, 3L, 4S, 5L, 7L, 9S, 10L and combinations of 1L-3L, collectively spanning approximately one-third of the maize genome, were examined for alterations in the expression of total protein profiles in scutellar tissue. The major effects found were negative correlations of specific proteins with the dosage of particular regions in a manner similar to that previously described for enzyme activity levels (Birchler 1979). Chromosome arms 1L, 4S and 5L produced the most severe negative effects, with 3L and 7L exhibiting this phenomenon to a lesser degree. Positive correlations of certain proteins were observed with the dosage of the 1L, 3L, 5L and 7L regions. The structural locus of one of the major scutellar proteins (PRO) is present in the long arm of chromosome 1 (Schwartz 1979), but exhibits compensation in a dosage series involving whole-arm comparisons. Multiple factors in 1L affect the level of the protein. The compound TB-1La-3L4759-3 (1L 0.20-0.39) has a slight negative effect on PRO, while TB-1La-3Le (1L 0.20-0.58) and TB-1La-3L5267 (1L 0.20-0.72) have a more pronounced negative influence. The level of this protein is not altered by the dosage of 3L. These observations suggest that compensation is brought about by the cancellation of a positive structural gene dosage effect by the negative inverse effect. Other regions of the genome that contribute to the control of PRO levels are 4S and 5L. Total protein profiles were also compared in haploid, diploid and tetraploid maize as a comparison to the aneuploid series. Most proteins exhibit structural-gene-dosage effects through the ploidy series, but others show a positive effect greater than expected from varying the structural genes. Still others are negatively affected by ploidy changes. In general, the ploidy alterations are not as great as predicted from the cumulative action of the aneuploid effects. The bearing of these observations on the biochemical basis of aneuploid syndromes is discussed.

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A STUDY OF ENZYME ACTIVITIES IN A DOSAGE SERIES OF THE LONG ARM OF CHROMOSOME ONE IN MAIZE

Genetics ◽

10.1093/genetics/92.4.1211 ◽

1979 ◽

Vol 92 (4) ◽

pp. 1211-1229

Author(s):

James A Birchler

Keyword(s):

Enzyme Activity ◽

Gene Dosage ◽

Dry Weight ◽

B Chromosome ◽

Chromosome 1 ◽

Activity Levels ◽

Structural Locus ◽

Gene Dosage Effect ◽

The One ◽

Number Of Cells

ABSTRACT The enzyme activity levels of alcohol, malate, isocitrate, glucose-6-phosphate and 6-phosphogluconate dehydrogenases were determined in mature maize scutella in a series of one to four doses of the long arm of chromosome 1, produced by the B-A translocation 1La. Although the Adh structural locus was varied, ADH levels did not exhibit a gene-dosage effect. The levels of GGPDH, GPGDH and IDH were negatively correlated with the dosage of 1L. MDH was unresponsive. The esterase-8 enzyme, whose structural locus was demonstrated to be elsewhere in the genome, was also negatively correlated with 1L dosage. The portion of the B chromosome involved in the translocation was shown to have no effect on the enzyme levels. Measurements of cell size and hydrolysable DNA per mg dry weight revealed no change in the number of cells through the one, two and three dose series. The topic of enzyme alterations in aneuploids is reviewed.

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THE GENETIC BASIS OF DOSAGE COMPENSATION OF ALCOHOL DEHYDROGENASE-1 IN MAIZE

Genetics ◽

10.1093/genetics/97.3-4.625 ◽

1981 ◽

Vol 97 (3-4) ◽

pp. 625-637 ◽

Cited By ~ 2

Author(s):

James A Birchler

Keyword(s):

Alcohol Dehydrogenase ◽

Structural Gene ◽

Dosage Compensation ◽

Genetic Basis ◽

Gene Dosage ◽

Dosage Effect ◽

Gene Dosage Effect ◽

Negative Effect ◽

Higher Eukaryotes ◽

Alcohol Dehydrogenase 1

ABSTRACT The levels of alcohol dehydrogenase (ADH) do not exhibit a structural gene-dosage effect in a one to four dosage series of the long arm of chromosome one (1L) (BIRCHLER19 79). This phenomenon, termed dosage compensation, has been studied in more detail. Experiments are described in which individuals aneuploid for shorter segments were examined for the level of ADH in order to characterize the genetic nature of the compensation. The relative ADH expression in segmental trisomics and tetrasomics of region IL 0.72–0.90, which includes the Adh locus, approaches the level expected from a strict gene dosage effect. Region IL 0.20–0.72 produces a negative effect upon ADH in a similar manner to that observed with other enzyme levels when IL as a whole is varied (BIRCHLEF1I9 79). These and other comparisons have led to the concept that the compensation of ADH results from the cancellation of the structural gene effect by the negative aneuploid effect. The example of ADH is discussed as a model for certain other cases of dosage compensation in higher eukaryotes.

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The HD-ZIP IV transcription factor Tril regulates fruit spine density through gene dosage effects in cucumber

Journal of Experimental Botany ◽

10.1093/jxb/eraa344 ◽

2020 ◽

Vol 71 (20) ◽

pp. 6297-6310

Author(s):

Hui Du ◽

Gang Wang ◽

Jian Pan ◽

Yue Chen ◽

Tingting Xiao ◽

...

Keyword(s):

Transcription Factor ◽

Genetic Interaction ◽

Gene Dosage ◽

Expression Patterns ◽

Tissue Expression ◽

Spine Density ◽

Gene Dosage Effect ◽

Gene Dosage Effects ◽

Transgenic Lines ◽

Mutant Phenotypes

Abstract Trichomes and fruit spines are important traits that directly affect the appearance quality and commercial value of cucumber (Cucumis sativus). Tril (Trichome-less), encodes a HD-Zip IV transcription factor that plays a crucial role in the initiation of trichomes and fruit spines, but little is known about the details of the regulatory mechanisms involved. In this study, analysis of tissue expression patterns indicated that Tril is expressed and functions in the early stages of organ initiation and development. Expression of Tril under the control of its own promoter (the TrilPro::Tril-3*flag fragment) could partly rescue the mutant phenotypes of tril, csgl3 (cucumber glabrous 3, an allelic mutant of tril), and fs1 (few spines 1, a fragment substitution in the Tril promoter region), providing further evidence that Tril is responsible for the initiation of trichomes and fruit spines. In lines with dense spine, fs1-type lines, and transgenic lines of different backgrounds containing the TrilPro::Tril-3*flag foreign fragment, spine density increased in conjunction with increases in Tril expression, indicating that Tril has a gene dosage effect on fruit spine density in cucumber. Numerous Spines (NS) is a negative regulatory factor of fruit spine density. Characterization of the molecular and genetic interaction between Tril and NS/ns demonstrated that Tril functions upstream of NS with respect to spine initiation. Overall, our results reveal a novel regulatory mechanism governing the effect of Tril on fruit spine development, and provide a reference for future work on breeding for physical quality in cucumber.

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Two-dimensional Gel Analysis of Proteins from Mouse Fetuses with Trisomy 19 after DEAE-Sepharose Chromatography

Genetics Research ◽

10.1017/s0016672300023120 ◽

1986 ◽

Vol 47 (3) ◽

pp. 193-197 ◽

Cited By ~ 6

Author(s):

Gerd H. Reichert

Keyword(s):

Gene Dosage ◽

Protein Pattern ◽

Polyacrylamide Gel Electrophoresis ◽

Two Dimensional ◽

Protein Patterns ◽

Gene Dosage Effect ◽

Gene Dosage Effects ◽

The Individual ◽

Mouse Fetuses ◽

Primary Gene

SummaryIsoelectrofocusing two-dimensional polyacrylamide gel electrophoresis (IEF-2D-PAGE) offers the opportunity to detect typical alterations in the protein pattern of trisomic mouse foetuses at a given time of development. The fractionation of the cell lysate by differential centrifugation into various subcellular components (nuclei, membranes, polyribosomes, cytoplasmic proteins) and fractionation of the proteins through DEAE-Sepharose chromatography allows detection of protein differences.It is possible to detect eight differences in the protein patterns between trisomy 19 (Ts 19) mouse foetuses and euploid mouse fetuses at day 15. Five of these differences are quantitative in nature, three are qualitative. One of these proteins is synthesized in Ts 19 foetuses at a higher level than in euploid mouse fetuses (primary gene dosage effect). The other seven proteins are reduced or not present in trisomic foetuses (consequences of primary gene dosage effects).The molecular mass of the individual proteins ranges from 13 to 41 kDa.

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On a regulatory gene controlling the expression of the murine lambda1 light chain.

Journal of Experimental Medicine ◽

10.1084/jem.148.5.1122 ◽

1978 ◽

Vol 148 (5) ◽

pp. 1122-1136 ◽

Cited By ~ 45

Author(s):

W Geckeler ◽

J Faversham ◽

M Cohn

Keyword(s):

Structural Gene ◽

Light Chain ◽

Gene Locus ◽

Germ Line ◽

Gene Dosage ◽

Regulatory Gene ◽

Transcriptional Unit ◽

Gene Dosage Effect ◽

Translocation Event ◽

V Genes

We describe here two alleles, an allele of the lambda1 locus present in the SJL strain (rlambda1lo) and an allele of the lambda1 locus present in the BALB/c strain (rlambda1 +), of a regulatory gene locus which specifically influences the expression of the mouse lambda1 light chain structural gene. The rlambda1 regulatory gene is not linked to either the major histocompatibility complex or to the heavy-chain allogroup but appears to be linked to the lambda1 structural gene locus. In the homozygous state, the present of the rlambda1lo allele results in a 50-fold reduction in the number of lambda1 antigen-sensitive, bone-marrow derived lymphocytes (ASCs) compared to the presence of the rlambda1 + allele. However, those few lambda1ASCs present in rlambda1lo homozygotes can be induced normally to produce lambda1 light chains indistinguishable from those found in rlambda1 + homozygotes. The reduction in lambda1ASC's due to the rlambda1lo allele results both in a reduction in the amount of lambda1 Ig in the serum and also in a large variation in the magnitude of the lambda1 antibody response to alpha(1,3) dextran by individual animals. This variation permits the estimate that, on the average, 50 B cells of anti-alpha(1,3) specificity must be present per animal to permit a measurable response. Surprisingly, the expression of a gene locus regulating lambda1 light chain expression (rlambda1 locus) shows a clear gene dosage effect with rlambda1lo/rlambda1 + heterozygotes having 1/2 the number of lambda1ASCs and 1/2 the amount of serum lambda1 Ig as rlambda1 +/rlambda1 + homozygotes. This fact permits an analysis of the relationship between germ-line v-genes and their individual expression in serum Ig. The rlambda1 locus controls specifically a DNA-level event which occurs in stem cells as they become committed to lambda1 light chain expression. We postulate that the rlambda1 locus represents one of the DNA level recognition sites involved in the translocation event which places the vlambda1 and clambda1 structural genes in a transcriptional unit.

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THE STRUCTURAL GENE FOR α-MANNOSIDASE-1 IN DICTYOSTELIUM DISCOIDEUM

Genetics ◽

10.1093/genetics/84.2.159 ◽

1976 ◽

Vol 84 (2) ◽

pp. 159-174

Author(s):

S J Free ◽

R T Schimke ◽

W F Loomis

Keyword(s):

Linkage Group ◽

Dictyostelium Discoideum ◽

Structural Gene ◽

Gene Dosage ◽

Dosage Effect ◽

Substrate Affinity ◽

Developmentally Regulated ◽

Group Vi ◽

Gene Dosage Effect

ABSTRACT We have isolated 4 independent mutations affecting α-mannosidase-1, a a developmentally regulated activity in Dictyostelium discoideum. Three of these result in a thermolabile α-mannosidase-1 activity. One mutation also affects the substrate affinity (Km) of the activity. In diploids these mutations show a gene dosage effect and are all alleles. The structural gene for α-mannosidase-1, as defined by these mutations, defines a new linkage group, linkage group VI. α-Mannosidase-1 is probably a homopolymer with subunits of 54,000 daltons.

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