Comparative Cyto-molecular Analysis of Repetitive DNA Provides Insights into the Differential Genome Structure and Evolution of Five Cucumis Species

Abstract Meiotic drive is the subversion of meiosis so that particular genes are preferentially transmitted to the progeny. Meiotic drive generally causes the preferential segregation of small regions of the genome; however, in maize we propose that meiotic drive is responsible for the evolution of large repetitive DNA arrays on all chromosomes. A maize meiotic drive locus found on an uncommon form of chromosome 10 [abnormal 10 (Ab10)] may be largely responsible for the evolution of heterochromatic chromosomal knobs, which can confer meiotic drive potential to every maize chromosome. Simulations were used to illustrate the dynamics of this meiotic drive model and suggest knobs might be deleterious in the absence of Ab10. Chromosomal knob data from maize's wild relatives (Zea mays ssp. parviglumis and mexicana) and phylogenetic comparisons demonstrated that the evolution of knob size, frequency, and chromosomal position agreed with the meiotic drive hypothesis. Knob chromosomal position was incompatible with the hypothesis that knob repetitive DNA is neutral or slightly deleterious to the genome. We also show that environmental factors and transposition may play a role in the evolution of knobs. Because knobs occur at multiple locations on all maize chromosomes, the combined effects of meiotic drive and genetic linkage may have reshaped genetic diversity throughout the maize genome in response to the presence of Ab10. Meiotic drive may be a major force of genome evolution, allowing revolutionary changes in genome structure and diversity over short evolutionary periods.

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Genome analysis and replication behavior of a set of repetitive sequences of Lilium longiflorum

Genome ◽

10.1139/g94-076 ◽

1994 ◽

Vol 37 (4) ◽

pp. 535-541

Author(s):

Nishan Jayawardene ◽

C. Daniel Riggs ◽

Clare A. Hasenkampf

Keyword(s):

Dna Replication ◽

Repetitive Dna ◽

Dna Sequences ◽

Genome Analysis ◽

Repetitive Sequences ◽

Genome Structure ◽

Lilium Longiflorum ◽

Chromosome Homology ◽

Replication Assay ◽

Expected Increase

The four clones, pLZH47, pLZ112, pLZ113, and pLZ122, previously assumed to contain DNA sequences that replicate during zygotene (zygDNA), actually had their replication behavior tested using a replication assay. Genome analysis was also done for each clone. All of the clones seem to be members of families of dispersed repetitive DNA. The number of copies per 2C genome are as follows: pLZH47, 13 500; pLZ112, >100; pLZ113, 200; and pLZ122, 3500. The replication assays measured the amount of hybridizable sequences available at the stage of leptotene (before zygotene DNA replication occurs) and at the stage of pachytene (after zygotene replication occurs). True zygDNA clones should have twice as many sequences to hybridize to at pachytene as at leptotene. None of the clones had the expected increase. One clone, pLZ122, did show a statistically significant increase (10%). It may consist of a mixture of zygDNA and non-zygDNA sequences. Alternatively, only 10% of the pLZ122 family members may function as zygDNA.Key words: meiosis, zygDNA sequences, synapsis, chromosome homology, genome structure.

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Intramolecular amplification of the tetracycline resistance determinant of transposon Tn1771 inEscherichia coli

Genetics Research ◽

10.1017/s0016672300018395 ◽

1979 ◽

Vol 33 (3) ◽

pp. 253-260 ◽

Cited By ~ 9

Author(s):

F. Schöffl ◽

A. Pühler

Keyword(s):

Molecular Structure ◽

Escherichia Coli ◽

Gene Amplification ◽

Molecular Analysis ◽

Repetitive Dna ◽

Tetracycline Resistance ◽

Conjugative Plasmid ◽

Resistance Determinant ◽

Inescherichia Coli ◽

Very High

SUMMARYStrains ofEscherichia coliharbouring a conjugative plasmid that carries a transposon for tetracycline resistance (Tn1771) were found to be adaptable to very high tetracycline concentrations. The molecular analysis of plasmids isolated from strains with enhanced levels of tetracycline resistance revealed an intramolecular amplification of the resistance determinant of the tetracycline transposon.A model for the molecular structure of the transposon is presented, which suggests that there are three repetitive DNA segments on Tn1771. This accounts for the properties both of transposition and of gene amplification.

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Molecular analysis of repetitive DNA elements from Entamoeba histolytica, which encode small RNAs and contain matrix/scaffold attachment recognition sequences

Molecular and Biochemical Parasitology ◽

10.1016/s0166-6851(02)00244-x ◽

2003 ◽

Vol 126 (1) ◽

pp. 35-42 ◽

Cited By ~ 9

Author(s):

Sulagna Banerjee ◽

Anuradha Lohia

Keyword(s):

Entamoeba Histolytica ◽

Molecular Analysis ◽

Repetitive Dna ◽

Small Rnas ◽

Dna Elements ◽

Repetitive Dna Elements

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Gene and Genome Structure in Diptera: Comparative Molecular Analysis of an Eye Colour Gene in Three Species

Ecological and Evolutionary Genetics of Drosophila ◽

10.1007/978-1-4684-8768-8_23 ◽

1990 ◽

pp. 337-358 ◽

Cited By ~ 1

Author(s):

Abigail Elizur ◽

Ygal Haupt ◽

Richard G. Tearle ◽

Antony J. Howells

Keyword(s):

Molecular Analysis ◽

Genome Structure ◽

Colour Gene ◽

Eye Colour

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Molecular analysis of neurotransmitter release

Essays in Biochemistry ◽

10.1042/bse0330029 ◽

1998 ◽

Vol 33 ◽

pp. 29-41 ◽

Cited By ~ 9

Author(s):

Giampietro Schiavo ◽

Gudrun Stenbeck

Keyword(s):

Molecular Analysis ◽

Neurotransmitter Release

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DNA methylation in satellite repeats disorders

Essays in Biochemistry ◽

10.1042/ebc20190028 ◽

2019 ◽

Vol 63 (6) ◽

pp. 757-771 ◽

Cited By ~ 4

Author(s):

Claire Francastel ◽

Frédérique Magdinier

Keyword(s):

Dna Methylation ◽

Human Genome ◽

Repetitive Dna ◽

Dna Sequences ◽

Satellite Repeats ◽

Tremendous Progress ◽

Genes Encoding ◽

Dna Elements ◽

Near Future

Abstract Despite the tremendous progress made in recent years in assembling the human genome, tandemly repeated DNA elements remain poorly characterized. These sequences account for the vast majority of methylated sites in the human genome and their methylated state is necessary for this repetitive DNA to function properly and to maintain genome integrity. Furthermore, recent advances highlight the emerging role of these sequences in regulating the functions of the human genome and its variability during evolution, among individuals, or in disease susceptibility. In addition, a number of inherited rare diseases are directly linked to the alteration of some of these repetitive DNA sequences, either through changes in the organization or size of the tandem repeat arrays or through mutations in genes encoding chromatin modifiers involved in the epigenetic regulation of these elements. Although largely overlooked so far in the functional annotation of the human genome, satellite elements play key roles in its architectural and topological organization. This includes functions as boundary elements delimitating functional domains or assembly of repressive nuclear compartments, with local or distal impact on gene expression. Thus, the consideration of satellite repeats organization and their associated epigenetic landmarks, including DNA methylation (DNAme), will become unavoidable in the near future to fully decipher human phenotypes and associated diseases.

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