rolling circle amplification
Recently Published Documents


TOTAL DOCUMENTS

916
(FIVE YEARS 300)

H-INDEX

71
(FIVE YEARS 13)

2022 ◽  
Author(s):  
Xiaoxia Han ◽  
Yue-Ying Li ◽  
Zi-Yue Wang ◽  
Ling-Zhi Liu ◽  
Bing-Jie Liu ◽  
...  

We develop for the first time a label-free fluorescent method for sensitive detection of fat mass and obesity-associated protein (FTO) activity using MazF-mediated primer generation rolling circle amplification. This method...


Animals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 76
Author(s):  
Faiz Padzil ◽  
Abdul Razak Mariatulqabtiah ◽  
Wen Siang Tan ◽  
Kok Lian Ho ◽  
Nurulfiza Mat Isa ◽  
...  

Over the years, development of molecular diagnostics has evolved significantly in the detection of pathogens within humans and their surroundings. Researchers have discovered new species and strains of viruses, while mitigating the viral infections that occur, owing to the accessibility of nucleic acid screening methods such as polymerase chain reaction (PCR), qualitative (real-time) polymerase chain reaction (qPCR) and reverse-transcription qPCR (RT-qPCR). While such molecular detection methods are widely utilized as the benchmark, the invention of isothermal amplifications has also emerged as a reliable tool to improvise on-field diagnosis without dependence on thermocyclers. Among the established isothermal amplification technologies are loop-mediated isothermal amplification (LAMP), recombinant polymerase amplification (RPA), strand displacement activity (SDA), nucleic acid sequence-based amplification (NASBA), helicase-dependent amplification (HDA) and rolling circle amplification (RCA). This review highlights the past research on and future prospects of LAMP, its principles and applications as a promising point-of-care diagnostic method against avian viruses.


2021 ◽  
Author(s):  
◽  
Matthew Rowe

<p>Over the past decade and a half, evidence for transfer of whole mitochondria between mammalian cells has emerged in the literature. The notion that mitochondria are restricted to the cell of origin has been overturned by this curious phenomenon, yet the physiological relevance of these transfer events remains unclear.   This thesis investigates intercellular mitochondrial transfer in co-cultures of neural cells in vitro, to understand whether neural cells placed under stress demonstrate an enhanced rate of intercellular mitochondrial transfer. This would implicate the phenomenon as a cellular response to stress.   Reliable techniques for quantitative study of intercellular mitochondrial transfer are limited so far in this field. To address this, a novel quantitative approach was developed to detect intercellular mitochondrial transfer, based on single molecule genotyping by target-primed rolling circle amplification. This enabled imaging of individual mitochondrial DNA molecules in situ, to detect those molecules which had moved between cells. Through this strategy, intercellular mitochondrial transfer was detected in new in vitro co-culture models.   Primary murine pericytes derived from brain microvessels, were found to readily transfer mitochondria to a murine astrocyte cell line in vitro. Cisplatin, a DNA damaging agent; and chloramphenicol, a mitochondrial ribosome inhibitor, used to induce acute cellular injuries in the murine astrocyte cell line. These injuries were characterised and found to induce apoptosis, cause changes in growth characteristics, mitochondrial gene expression, and alter the metabolic phenotype of the cells. A derivative of the astrocyte cell line which completely lacks mitochondrial respiration, was found to model a chronic metabolic injury.  As pericytes are prevalent throughout the brain, the pericyte/astrocyte co-culture model was selected to evaluate how the rate of intercellular mitochondrial transfer was altered, when the astrocytes were injured prior to co-culture. Through in situ single molecule genotyping and high throughput confocal microscopy, quantitative data was produced on how the rate of intercellular mitochondrial transfer was altered by injury in these models. The rate of intercellular mitochondrial transfer remained unaltered by chloramphenicol, however both cisplatin and the chronic metabolic injury model demonstrated reduced numbers of pericyte mitochondrial DNAs transferred into the injured astrocytes.   These studies demonstrate successful application of a novel approach to study intercellular mitochondrial transfer and enable quantitative studies of this phenomenon.</p>


2021 ◽  
Author(s):  
◽  
Matthew Rowe

<p>Over the past decade and a half, evidence for transfer of whole mitochondria between mammalian cells has emerged in the literature. The notion that mitochondria are restricted to the cell of origin has been overturned by this curious phenomenon, yet the physiological relevance of these transfer events remains unclear.   This thesis investigates intercellular mitochondrial transfer in co-cultures of neural cells in vitro, to understand whether neural cells placed under stress demonstrate an enhanced rate of intercellular mitochondrial transfer. This would implicate the phenomenon as a cellular response to stress.   Reliable techniques for quantitative study of intercellular mitochondrial transfer are limited so far in this field. To address this, a novel quantitative approach was developed to detect intercellular mitochondrial transfer, based on single molecule genotyping by target-primed rolling circle amplification. This enabled imaging of individual mitochondrial DNA molecules in situ, to detect those molecules which had moved between cells. Through this strategy, intercellular mitochondrial transfer was detected in new in vitro co-culture models.   Primary murine pericytes derived from brain microvessels, were found to readily transfer mitochondria to a murine astrocyte cell line in vitro. Cisplatin, a DNA damaging agent; and chloramphenicol, a mitochondrial ribosome inhibitor, used to induce acute cellular injuries in the murine astrocyte cell line. These injuries were characterised and found to induce apoptosis, cause changes in growth characteristics, mitochondrial gene expression, and alter the metabolic phenotype of the cells. A derivative of the astrocyte cell line which completely lacks mitochondrial respiration, was found to model a chronic metabolic injury.  As pericytes are prevalent throughout the brain, the pericyte/astrocyte co-culture model was selected to evaluate how the rate of intercellular mitochondrial transfer was altered, when the astrocytes were injured prior to co-culture. Through in situ single molecule genotyping and high throughput confocal microscopy, quantitative data was produced on how the rate of intercellular mitochondrial transfer was altered by injury in these models. The rate of intercellular mitochondrial transfer remained unaltered by chloramphenicol, however both cisplatin and the chronic metabolic injury model demonstrated reduced numbers of pericyte mitochondrial DNAs transferred into the injured astrocytes.   These studies demonstrate successful application of a novel approach to study intercellular mitochondrial transfer and enable quantitative studies of this phenomenon.</p>


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Hongke Qu ◽  
Chunmei Fan ◽  
Mingjian Chen ◽  
Xiangyan Zhang ◽  
Qijia Yan ◽  
...  

AbstractThe cyclic signal amplification technology has been widely applied for the ultrasensitive detection of many important biomolecules, such as nucleic acids, proteins, enzymes, adenosine triphosphate (ATP), metal ions, exosome, etc. Due to their low content in the complex biological samples, traditional detection methods are insufficient to satisfy the requirements for monitoring those biomolecules. Therefore, effective and sensitive biosensors based on cyclic signal amplification technology are of great significance for the quick and simple diagnosis and treatment of diseases. Fluorescent biosensor based on cyclic signal amplification technology has become a research hotspot due to its simple operation, low cost, short time, high sensitivity and high specificity. This paper introduces several cyclic amplification methods, such as rolling circle amplification (RCA), strand displacement reactions (SDR) and enzyme-assisted amplification (EAA), and summarizes the research progress of using this technology in the detection of different biomolecules in recent years, in order to provide help for the research of more efficient and sensitive detection methods. Graphical Abstract


Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2385
Author(s):  
Aamir Lal ◽  
Yong-Ho Kim ◽  
Thuy Thi Bich Vo ◽  
I Gusti Ngurah Prabu Wira Sanjaya ◽  
Phuong Thi Ho ◽  
...  

Fraxinus rhynchophylla, common name ash, belongs to the family Oleaceae and is found in China, Korea, North America, the Indian subcontinent, and eastern Russia. It has been used as a traditional herbal medicine in Korea and various parts of the world due to its chemical constituents. During a field survey in March 2019, mild vein thickening (almost negligible) was observed in a few ash trees. High-throughput sequencing of libraries of total DNA from ash trees, rolling-circle amplification (RCA), and polymerase chain reaction (PCR) allowed the identification of a Fraxinus symptomless virus. This virus has five confirmed open reading frames along with a possible sixth open reading frame that encodes the movement protein and is almost 2.7 kb in size, with a nonanucleotide and stem loop structure identical to begomoviruses. In terms of its size and structure, this virus strongly resembles begomoviruses, but does not show any significant sequence identity with them. To confirm movement of the virus within the trees, different parts of infected trees were examined, and viral movement was successfully observed. No satellite molecules or DNA B were identified. Two-step PCR confirmed the virion and complementary strands during replication in both freshly collected infected samples of ash tree and Nicotiana benthamiana samples agro-inoculated with infectious clones. This taxon is so distantly grouped from other known geminiviruses that it likely represents a new geminivirus genus.


Sign in / Sign up

Export Citation Format

Share Document