A Unified Matrix Hypothesis of DNA-directed morphogenesis, protodynamism and growth control

1988 ◽  
Vol 8 (6) ◽  
pp. 669-669
Author(s):  
Klaus Scherrer
Keyword(s):  
Nuclear Dna ◽  
Growth Control ◽  
Theoretical Concept ◽  
Protein Coding ◽  
Basic Proposition ◽  
C Value ◽  
Eukaryotic Organisms ◽  
And Function ◽  
Chromosome Organisation ◽  
Morphological Patterns

A theoretical concept is proposed, in order to explain some enigmatic aspects of cellular and molecular biology of eukaryotic organisms. Among these are the C-value paradox of DNA redundancy, the correlation of DNA content and cell size, the disruption of genes at DNA level, the “Chromosome field” data of Lima de Faria (Hereditas93:1, 1980), the “quantal mitosis proposition” of Holtzer et al. (Curr. Top. Dev. Biol.7:229, 1972), the inheritance of morphological patterns, the relations of DNA and chromosome organisation to cellular structure and function, the molecular basis of speciation, etc. The basic proposition of the “Unified Matrix Hypothesis” is that the nuclear DNA has a direct morphogenic function, in addition to its coding function in protein synthesis. This additional genetic information is thought to be largely contained in the non-protein coding transcribed DNA, and in the untranscribed part of the genome.

A unified matrix hypothesis of DNA-directed morphogenesis, protodynamism and growth control1

1989 ◽  
Vol 9 (2) ◽  
pp. 157-188 ◽  
Author(s):  
Klaus Scherrer
Keyword(s):  
Nuclear Dna ◽  
Theoretical Concept ◽  
Structure And Function ◽  
Protein Coding ◽  
Basic Proposition ◽  
C Value ◽  
Eukaryotic Organisms ◽  
And Function ◽  
Chromosome Organisation ◽  
Morphological Patterns

A theoretical concept is proposed, in order to explain some enigmatic aspects of cellular and molecular biology of eukaryotic organisms. Among these are the C-value paradox of DNA redundancy, the correlation of DNA content and cell size, the disruption of genes at DNA level, the “Chromosome field” data of Lima de Faria (Hereditas93:1, 1980), the “quantal mitosis” proposition of Holtzer et al. (Curr. Top. Dev. Biol.7:229 1972), the inheritance of morphological patterns, the relations of DNA and chromosome organisation to cellular structure and function, the molecular basis of speciation, etc. The basic proposition of the “Unified Matrix Hypothesis” is that the nuclear DNA has a direct morphogenic function, in addition to its coding function in protein synthesis. This additional genetic information is thought to be largely contained in the non-protein coding transcribed DNA, and in the untranscribed part of the genome.

scholarly journals Common and rare genetic variants that could contribute to severe otitis media in an Australian Aboriginal population

2021 ◽  
Author(s):  
Sarra E Jamieson ◽  
Michaela Fakiola ◽  
Dave Tang ◽  
Elizabeth Scaman ◽  
Genevieve Syn ◽  
...  
Keyword(s):  
Hair Cell ◽  
Otitis Media ◽  
Genetic Risk ◽  
Transforming Growth Factor ◽  
Rare Variants ◽  
Protein Coding ◽  
Gene Sets ◽  
Growth Factor Signalling ◽  
Rare Genetic Variants ◽  
And Function

Abstract Background Our goal was to identify genetic risk factors for severe otitis media (OM) in Aboriginal Australians. Methods Illumina ® Omni2.5 BeadChip and imputed data were compared between 21 children with severe OM (multiple episodes chronic suppurative OM and/or perforations or tympanic sclerosis) and 370 individuals without this phenotype, followed by FUnctional Mapping and Annotation (FUMA). Exome data filtered for common (EXaC_all≥0.1) putative deleterious variants influencing protein coding (CADD-scaled scores ≥ 15) were used to compare 15 severe OM cases with 9 mild cases (single episode of acute OM recorded over ≥ 3 consecutive years). Rare (ExAC_all≤0.01) such variants were filtered for those present only in severe OM. Enrichr was used to determine enrichment of genes contributing to pathways/processes relevant to OM. Results FUMA analysis identified two plausible genetic risk loci for severe OM: NR3C1 (Pimputed_1000G=3.62x10 -6) encoding the glucocorticoid receptor, and NREP (Pimputed_1000G=3.67x10 -6) encoding neuronal regeneration related protein. Exome analysis showed: (i) association of severe OM with variants influencing protein coding (CADD-scaled ≥ 15) in a gene-set (GRXCR1, CDH23, LRP2, FAT4, ARSA, EYA4) enriched for Mammalian Phenotype Level 4 abnormal hair cell stereociliary bundle morphology and related phenotypes; (ii) rare variants influencing protein coding only seen in severe OM provided gene-sets enriched for “abnormal ear” (LMNA, CDH23, LRP2, MYO7A, FGFR1), integrin interactions, transforming growth factor signalling, and cell projection phenotypes including hair cell stereociliary bundles and cilium assembly. Conclusions This study highlights interacting genes and pathways related to cilium structure and function that may contribute to extreme susceptibility to OM in Aboriginal Australian children.

scholarly journals The Schizosaccharomyces pombe cho1+ Gene Encodes a Phospholipid Methyltransferase

Genetics ◽  
1998 ◽  
Vol 150 (2) ◽  
pp. 553-562
Author(s):  
Margaret I Kanipes ◽  
John E Hill ◽  
Susan A Henry
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Sequence Analysis ◽  
Schizosaccharomyces Pombe ◽  
Gene Disruption ◽  
Structure And Function ◽  
Biosynthetic Enzyme ◽  
Gene Encoding ◽  
Complementation Groups ◽  
Eukaryotic Organisms ◽  
And Function

Abstract The isolation of mutants of Schizosaccharomyces pombe defective in the synthesis of phosphatidylcholine via the methylation of phosphatidylethanolamine is reported. These mutants are choline auxotrophs and fall into two unlinked complementation groups, cho1 and cho2. We also report the analysis of the cho1+ gene, the first structural gene encoding a phospholipid biosynthetic enzyme from S. pombe to be cloned and characterized. The cho1+ gene disruption mutant (cho1Δ) is viable if choline is supplied and resembles the cho1 mutants isolated after mutagenesis. Sequence analysis of the cho1+ gene indicates that it encodes a protein closely related to phospholipid methyltransferases from Saccharomyces cerevisiae and rat. Phospholipid methyltransferases encoded by a rat liver cDNA and the S. cerevisiae OPI3 gene are both able to complement the choline auxotrophy of the S. pombe cho1 mutants. These results suggest that both the structure and function of the phospholipid N-methyltransferases are broadly conserved among eukaryotic organisms.

scholarly journals Commuting to Work: Nucleolar Long Non-Coding RNA Control Ribosome Biogenesis from Near and Far

2021 ◽  
Vol 7 (3) ◽  
pp. 42
Author(s):  
Victoria Mamontova ◽  
Barbara Trifault ◽  
Lea Boten ◽  
Kaspar Burger
Keyword(s):  
Gene Expression ◽  
Rna Polymerase Ii ◽  
Ribosome Biogenesis ◽  
Intergenic Spacer ◽  
Cellular Growth ◽  
Rrna Synthesis ◽  
Protein Coding ◽  
Non Coding Rna ◽  
And Function ◽  
In Cis

Gene expression is an essential process for cellular growth, proliferation, and differentiation. The transcription of protein-coding genes and non-coding loci depends on RNA polymerases. Interestingly, numerous loci encode long non-coding (lnc)RNA transcripts that are transcribed by RNA polymerase II (RNAPII) and fine-tune the RNA metabolism. The nucleolus is a prime example of how different lncRNA species concomitantly regulate gene expression by facilitating the production and processing of ribosomal (r)RNA for ribosome biogenesis. Here, we summarise the current findings on how RNAPII influences nucleolar structure and function. We describe how RNAPII-dependent lncRNA can both promote nucleolar integrity and inhibit ribosomal (r)RNA synthesis by modulating the availability of rRNA synthesis factors in trans. Surprisingly, some lncRNA transcripts can directly originate from nucleolar loci and function in cis. The nucleolar intergenic spacer (IGS), for example, encodes nucleolar transcripts that counteract spurious rRNA synthesis in unperturbed cells. In response to DNA damage, RNAPII-dependent lncRNA originates directly at broken ribosomal (r)DNA loci and is processed into small ncRNA, possibly to modulate DNA repair. Thus, lncRNA-mediated regulation of nucleolar biology occurs by several modes of action and is more direct than anticipated, pointing to an intimate crosstalk of RNA metabolic events.

Long Noncoding RNAs in Plants

2021 ◽  
Vol 72 (1) ◽  
Author(s):  
Andrzej T. Wierzbicki ◽  
Todd Blevins ◽  
Szymon Swiezewski
Keyword(s):  
Gene Expression ◽  
Nuclear Dna ◽  
Noncoding Rnas ◽  
Chromatin Accessibility ◽  
Long Noncoding Rnas ◽  
Annual Review ◽  
Publication Date ◽  
Protein Coding ◽  
Ribonucleic Acids ◽  
Coding Potential

Plants have an extraordinary diversity of transcription machineries, including five nuclear DNA-dependent RNA polymerases. Four of these enzymes are dedicated to the production of long noncoding RNAs (lncRNAs), which are ribonucleic acids with functions independent of their protein-coding potential. lncRNAs display a broad range of lengths and structures, but they are distinct from the small RNA guides of RNA interference (RNAi) pathways. lncRNAs frequently serve as structural, catalytic, or regulatory molecules for gene expression. They can affect all elements of genes, including promoters, untranslated regions, exons, introns, and terminators, controlling gene expression at various levels, including modifying chromatin accessibility, transcription, splicing, and translation. Certain lncRNAs protect genome integrity, while others respond to environmental cues like temperature, drought, nutrients, and pathogens. In this review, we explain the challenge of defining lncRNAs, introduce the machineries responsible for their production, and organize this knowledge by viewing the functions of lncRNAs throughout the structure of a typical plant gene. Expected final online publication date for the Annual Review of Plant Biology, Volume 72 is May 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

scholarly journals The structure and function of centriolar rootlets

2021 ◽  
Vol 134 (16) ◽  
Author(s):  
Robert Mahen
Keyword(s):  
Cellular Function ◽  
Structure And Function ◽  
Cellular Systems ◽  
Macromolecular Assemblies ◽  
Cellular Processes ◽  
Holistic Understanding ◽  
Eukaryotic Organisms ◽  
And Function ◽  
Knockout Animals

ABSTRACT To gain a holistic understanding of cellular function, we must understand not just the role of individual organelles, but also how multiple macromolecular assemblies function collectively. Centrioles produce fundamental cellular processes through their ability to organise cytoskeletal fibres. In addition to nucleating microtubules, centrioles form lesser-known polymers, termed rootlets. Rootlets were identified over a 100 years ago and have been documented morphologically since by electron microscopy in different eukaryotic organisms. Rootlet-knockout animals have been created in various systems, providing insight into their physiological functions. However, the precise structure and function of rootlets is still enigmatic. Here, I consider common themes of rootlet function and assembly across diverse cellular systems. I suggest that the capability of rootlets to form physical links from centrioles to other cellular structures is a general principle unifying their functions in diverse cells and serves as an example of how cellular function arises from collective organellar activity.

scholarly journals Cellular heterogeneity in pressure and growth emerges from tissue topology and geometry

2018 ◽  
Author(s):  
Yuchen Long ◽  
Ibrahim Cheddadi ◽  
Vincent Mirabet ◽  
Gabriella Mosca ◽  
Mathilde Dumond ◽  
...  
Keyword(s):  
Water Movement ◽  
Turgor Pressure ◽  
Growth Control ◽  
Cellular Growth ◽  
Cellular Heterogeneity ◽  
Tissue Water ◽  
Water Conductivity ◽  
Force Microscopy ◽  
Atomic Force ◽  
And Function

Cell-to-cell heterogeneity prevails in many biological systems, although its origin and function are often unclear. Cell hydrostatic pressure, alias turgor pressure, is essential in physiology and morphogenesis, and its spatial variations are often overlooked. Here, based on a mathematical model describing cell mechanics and water movement in a plant tissue, we predict that cell pressure anticorrelates with cell neighbour number. Using atomic force microscopy, we confirm this prediction in the Arabidopsis shoot apical meristem, a population of stem cells that generate all plant aerial organs. Pressure is predicted to correlate either positively or negatively with cellular growth rate depending on osmotic drive, cell wall extensibility, and hydraulic conductivity. The meristem exhibits one of these two regimes depending on conditions, suggesting that, in this tissue, water conductivity is non-negligible in growth control. Our results illustrate links between local topology, cell mechanical state and cell growth, with potential roles in tissue homeostasis.

scholarly journals HOTAIR: An Oncogenic Long Non-Coding RNA in Human Cancer

2018 ◽  
Vol 47 (3) ◽  
pp. 893-913 ◽  
Author(s):  
Qing Tang ◽  
Swei Sunny Hann
Keyword(s):  
Drug Resistance ◽  
Human Cancer ◽  
Critical Role ◽  
Stem Cell Differentiation ◽  
Human Diseases ◽  
Biological Functions ◽  
Protein Coding ◽  
Non Coding Rna ◽  
And Function ◽  
Long Non Coding Rna

Long non-coding RNAs (LncRNAs) represent a novel class of noncoding RNAs that are longer than 200 nucleotides without protein-coding potential and function as novel master regulators in various human diseases, including cancer. Accumulating evidence shows that lncRNAs are dysregulated and implicated in various aspects of cellular homeostasis, such as proliferation, apoptosis, mobility, invasion, metastasis, chromatin remodeling, gene transcription, and post-transcriptional processing. However, the mechanisms by which lncRNAs regulate various biological functions in human diseases have yet to be determined. HOX antisense intergenic RNA (HOTAIR) is a recently discovered lncRNA and plays a critical role in various areas of cancer, such as proliferation, survival, migration, drug resistance, and genomic stability. In this review, we briefly introduce the concept, identification, and biological functions of HOTAIR. We then describe the involvement of HOTAIR that has been associated with tumorigenesis, growth, invasion, cancer stem cell differentiation, metastasis, and drug resistance in cancer. We also discuss emerging insights into the role of HOTAIR as potential biomarkers and therapeutic targets for novel treatment paradigms in cancer.

scholarly journals The Roles of Long Noncoding RNAs HNF1α-AS1 and HNF4α-AS1 in Drug Metabolism and Human Diseases

2020 ◽  
Vol 6 (2) ◽  
pp. 24 ◽  
Author(s):  
Liming Chen ◽  
Yifan Bao ◽  
Suzhen Jiang ◽  
Xiao-bo Zhong
Keyword(s):  
Drug Metabolism ◽  
Drug Toxicity ◽  
Target Genes ◽  
Noncoding Rnas ◽  
Long Noncoding Rnas ◽  
Future Directions ◽  
Protein Coding ◽  
Mirna Sponge ◽  
Current Review ◽  
And Function

Long noncoding RNAs (lncRNAs) are RNAs with a length of over 200 nucleotides that do not have protein-coding abilities. Recent studies suggest that lncRNAs are highly involved in physiological functions and diseases. lncRNAs HNF1α-AS1 and HNF4α-AS1 are transcripts of lncRNA genes HNF1α-AS1 and HNF4α-AS1, which are antisense lncRNA genes located in the neighborhood regions of the transcription factor (TF) genes HNF1α and HNF4α, respectively. HNF1α-AS1 and HNF4α-AS1 have been reported to be involved in several important functions in human physiological activities and diseases. In the liver, HNF1α-AS1 and HNF4α-AS1 regulate the expression and function of several drug-metabolizing cytochrome P450 (P450) enzymes, which also further impact P450-mediated drug metabolism and drug toxicity. In addition, HNF1α-AS1 and HNF4α-AS1 also play important roles in the tumorigenesis, progression, invasion, and treatment outcome of several cancers. Through interacting with different molecules, including miRNAs and proteins, HNF1α-AS1 and HNF4α-AS1 can regulate their target genes in several different mechanisms including miRNA sponge, decoy, or scaffold. The purpose of the current review is to summarize the identified functions and mechanisms of HNF1α-AS1 and HNF4α-AS1 and to discuss the future directions of research of these two lncRNAs.

Oxidative stress-induced cell death of human oral neutrophils

2003 ◽  
Vol 284 (4) ◽  
pp. C1048-C1053 ◽  
Author(s):  
Eisuke F. Sato ◽  
Masahiro Higashino ◽  
Kazuo Ikeda ◽  
Ryotaro Wake ◽  
Mitsuyoshi Matsuo ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Tyrosine Kinase ◽  
Protein Tyrosine Kinase ◽  
Caspase 3 ◽  
Nuclear Dna ◽  
Kinase Inhibitor ◽  
Tissue Injury ◽  
Morphological Changes ◽  
Limited Information ◽  
And Function

Polymorphonuclear leukocytes (PMN) play crucial roles in protecting hosts against invading microbes and in the pathogenesis of inflammatory tissue injury. Although PMN migrate into mucosal layers of digestive and respiratory tracts, only limited information is available of their fate and function in situ. We previously reported that, unlike circulating PMN (CPMN), PMN in the oral cavity spontaneously generate superoxide radical and nitric oxide (NO) in the absence of any stimuli. When cultured for 12 h under physiological conditions, oral PMN (OPMN) showed morphological changes that are characteristic of those of apoptosis. Upon agarose gel electrophoresis, nuclear DNA samples isolated from OPMN revealed ladder-like profiles characteristic of nucleosomal fragmentation.l-cysteine, reduced glutathione (GSH), and herbimycin A, a protein tyrosine kinase inhibitor, suppressed the activation of caspase-3 and apoptosis of OPMN. Neither thiourea, superoxide dismutase (SOD), nor catalase inhibited the activation of caspase-3 and apoptosis. Moreover, N-acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO), inhibitor for caspase-3, inhibited the fragmentation of DNA. These results suggested that oxidative stress and/or tyrosine-kinase-dependent pathway(s) activated caspase-3 in OPMN, thereby inducing their apoptosis.

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