MITOCHONDRIAL VARIANTS OF NEUROSPORA INTERMEDIA FROM NATURE

1982 ◽  
Vol 24 (6) ◽  
pp. 741-759 ◽  
Author(s):  
A. Rieck ◽  
A. J. F. Griffiths ◽  
H. Bertrand
Keyword(s):  
Genetic Alterations ◽  
Growth Patterns ◽  
Ribosome Assembly ◽  
Normal Strain ◽  
Mitochondrial Cytochrome ◽  
Neurospora Intermedia ◽  
Mitochondrial Ribosome ◽  
The World ◽  
Standard Normal ◽  
Natural Isolates

From a sample of 122 natural isolates of Neurospora intermedia collected recently from around the world, five variants had erratic stop-start growth patterns reminiscent of the phenotype of "stopper" laboratory extranuclear mutants of Neurospora crassa. Like laboratory isolated mutants, the natural "stopper" variants were sterile as protoperithecial parents and transmitted the variant growth phenotypes very inefficiently, if at all, as male parents. Heterokaryon tests could not be made because of strain incompatibilities. Four of the variants have mitochondrial cytochrome aa3 and b deficiencies. These four variants are all defective in mitochondrial ribosome assembly and have abnormal ratios of large to small subunits. Restriction enzyme analyses revealed some similarity of N. intermedia to N. crassa mtDNA. One normal and four variant strains had additional DNA in comparison to a standard normal strain. Cumulatively, the results indicate that the genetic alterations which cause stopper phenotypes of these natural isolates of N. intermedia are of mitochondrial rather than nuclear origin.

Population Genetics ofCaenorhabditis elegans: The Paradox of Low Polymorphism in a Widespread Species

Genetics ◽  
2003 ◽  
Vol 163 (1) ◽  
pp. 147-157 ◽  
Author(s):  
Arjun Sivasundar ◽  
Jody Hey
Keyword(s):  
Genetic Variation ◽  
Microsatellite Loci ◽  
Population Expansion ◽  
Widespread Species ◽  
C Elegans ◽  
Model Research ◽  
The World ◽  
Natural Isolates ◽  
History Of ◽  
Low Levels

AbstractCaenorhabditis elegans has become one of the most widely used model research organisms, yet we have little information on evolutionary processes and recent evolutionary history of this widespread species. We examined patterns of variation at 20 microsatellite loci in a sample of 23 natural isolates of C. elegans from various parts of the world. One-half of the loci were monomorphic among all strains, and overall genetic variation at microsatellite loci was low, relative to most other species. Some population structure was detected, but there was no association between the genetic and geographic distances among different natural isolates. Thus, despite the nearly worldwide occurrence of C. elegans, little evidence was found for local adaptation in strains derived from different parts of the world. The low levels of genetic variation within and among populations suggest that recent colonization and population expansion might have occurred. However, the patterns of variation are not consistent with population expansion. A possible explanation for the observed patterns is the action of background selection to reduce polymorphism, coupled with ongoing gene flow among populations worldwide.

scholarly journals Stepwise maturation of the peptidyl transferase region of human mitoribosomes

2021 ◽  
Author(s):  
Tea Lenarcic ◽  
Mateusz Jaskolowski ◽  
Marc Leibundgut ◽  
Alain Scaiola ◽  
Tanja Schoenhut ◽  
...  
Keyword(s):  
Quality Control ◽  
16S Rrna ◽  
Active Site ◽  
Critical Role ◽  
Ribosomal Subunit ◽  
Structural Basis ◽  
Ribosome Assembly ◽  
Peptidyl Transferase ◽  
Mitochondrial Ribosomes ◽  
Mitochondrial Ribosome

Mitochondrial ribosomes are specialized for the synthesis of membrane proteins responsible for oxidative phosphorylation. Mammalian mitoribosomes diverged considerably from the ancestral bacterial ribosomes and feature dramatically reduced ribosomal RNAs. Structural basis of the mammalian mitochondrial ribosome assembly is currently not understood. Here we present eight distinct assembly intermediates of the human large mitoribosomal subunit involving 7 assembly factors. We discover that NSUN4-MTERF4 dimer plays a critical role in the process by stabilizing the 16S rRNA in a conformation that exposes the functionally important regions of rRNA for modification by MRM2 methyltransferase and quality control interactions with a conserved mitochondrial GTPase MTG2 that contacts the sarcin ricin loop and the immature active site. The successive action of these factors leads to the formation of the peptidyl transferase active site of the mitoribosome and the folding of the surrounding rRNA regions responsible for interactions with tRNAs and the small ribosomal subunit.

scholarly journals Hierarchical RNA Processing Is Required for Mitochondrial Ribosome Assembly

Cell Reports ◽  
2016 ◽  
Vol 16 (7) ◽  
pp. 1874-1890 ◽  
Author(s):  
Oliver Rackham ◽  
Jakob D. Busch ◽  
Stanka Matic ◽  
Stefan J. Siira ◽  
Irina Kuznetsova ◽  
...  
Keyword(s):  
Rna Processing ◽  
Ribosome Assembly ◽  
Mitochondrial Ribosome

scholarly journals The first record of the Siberian northern shrike (Lanius borealis sibiricus) in Lithuania with molecular confirmation

Biologija ◽  
2020 ◽  
Vol 66 (1) ◽  
Author(s):  
Vytautas Eigirdas ◽  
Vesta Jonikė
Keyword(s):  
Climate Change ◽  
New Species ◽  
Biological Diversity ◽  
Bird Species ◽  
First Record ◽  
Mitochondrial Cytochrome ◽  
The Past ◽  
Mitochondrial Cytochrome B ◽  
The World ◽  
A New Species

Climate change significantly affects biological diversity around the world. Trends of this phenomenon have also been noticed in Lithuania: in the past decades, 55 new bird species have been recorded. The recent record of a new species was done on 3 December 2019. During ordinary birds ringing carried out in Ventės Ragas Ornithological Station in Lithuania, an individual Siberian northern shrike (Lanius borealis sibiricus) was caught and ringed. Additional blood sample was collected for species confirmation. Based on identification keys and molecular mitochondrial cytochrome b analysis, we report that this is the first record of the Siberian northern shrike in Lithuania.

scholarly journals Productivity Growth: Patterns and Determinants across the World

Economía ◽  
2019 ◽  
Vol 42 (84) ◽  
pp. 36-93
Author(s):  
Young Eun Kim ◽  
Norman V. Loayza
Keyword(s):  
Productivity Growth ◽  
Growth Patterns ◽  
The World

scholarly journals Cáncer en fauna silvestre

2021 ◽  
Vol 5 (13) ◽  
pp. 47-60
Author(s):  
Marina Guadarrama Olhovich
Keyword(s):  
Animal Species ◽  
Inflammatory Diseases ◽  
Environmental Pollutants ◽  
Genetic Alterations ◽  
Infectious Agents ◽  
Chronic Inflammatory Diseases ◽  
The World ◽  
Different Types

There are different types of cancer that occur for different reasons: genetic alterations, environmental pollutants, infectious agents, chronic inflammatory diseases, and so on. Although not exactly known all the causes that can trigger it, it has been proven that in many cases its origin can be the same in humans and animals, not only domestic, but also wild, including rhinos, jaguars, deer, elephants, which can develop this disease but because of the conditions where they live, it is difficult to care for them. Here we will review how some animal species in certain parts of the world have some types of cancer, that being in other places or if they were of another species they would not develop it, and we can also understand how there are families of individuals with cancer and others not. As well as the influence of the environment and certain diseases that can lead to this condition.

scholarly journals The Generalized-Growth Modeling of COVID-19

2021 ◽  
Vol 8 ◽  
Author(s):  
Ye Wu ◽  
Lin Zhang ◽  
Wenjing Cao ◽  
Xiaofei Liu ◽  
Xin Feng
Keyword(s):  
Growth Model ◽  
Growth Modeling ◽  
Phenomenological Approach ◽  
Growth Patterns ◽  
Crucial Importance ◽  
The World ◽  
Global Spread ◽  
General Dynamics

The global spread of the COVID-19 pandemic is changing everything in 2020. It is of crucial importance to characterize the growth patterns during the transmission. In this paper, a generalized-growth model is established to present the evolution of the number of the total confirmed cases changing with time. Due to effective containment, the generalized growth model reveals a piecewise pattern, referred to as the sub-exponential and the sub-linear stages. Moreover, the parameters can quantify the effectiveness of the containment and the trend of resurgence in different regions all over the world. Our model provides a phenomenological approach, which is simple and transparent for better understanding of the typical patterns within the general dynamics. Our model may have implications for possible nowcasting and forecasting of the pandemic trend.

scholarly journals Biosynthesis of Polyhydroxyalkanoate by Recombinant Bacteria: A Review

2021 ◽  
pp. 218-225
Author(s):  
Gamal Gabr ◽  
Nahla M. M. Hassan
Keyword(s):  
Heart Valves ◽  
Structural Diversity ◽  
Medical Applications ◽  
Structural Studies ◽  
Recombinant Bacteria ◽  
Major Interest ◽  
The World ◽  
Natural Isolates ◽  
Pha Production ◽  
High Degree

Polyhydroxyalkanoates (PHAs), a biodegradable polymer, has many industrial and medical applications such as heart valves, scaffold, suture and drug delivery. Because of their structural diversity and close analogy to plastics, PHAs have gained major interest over the world. Natural isolates, recombinant bacteria, and plants have all been found to improve the quality, quantity, and economics of PHA production. Their biodegradability makes them an especially appealing synthetic plastic substitute. PHB biosynthetic genes phbA, phbB, and phbC are grouped and systematised into a single phbCAB operon. In terms of alignment and clustering of the relevant genes, the PHB pathway varies greatly across bacterial genera. In this regard, the enzymes appear to have a high degree of sequence preservation. The structural studies further improve the mechanism of action of these enzymes and helped in improving and choosing the good candidates for increased production of PHB.

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