siRNA / RNAi /miRNA transfection Rat Ar4-2j (Pancreatic tumor)

Get tips on using miRNeasy Serum/Plasma Advanced Kit (50) to perform RNA isolation / purification Tissue - Livestock Blood / Serum / Plasma / Buffy coat

Reporter gene assays are designed to test the regulation of the expression of a gene of interest. This is usually done by linking the promoter of the gene of interest with a gene such as a firefly luciferase, which can be easily detected by addition of luciferin that leads to an enzymatic reaction to produce luminescence. The enzymatic reaction can be correlated to the expression of the gene of interest. Another luciferase gene that can be used is Renilla luciferase. For an appropriate luciferase assay: 1. the reporter should express uniformly in all cells, 2. specifically respond to effectors that the assay intends to monitor, 3. have low intrinsic stability to quickly reflect transcriptional dynamics. It is important to have an equal number of cells plated in each testing condition to avoid any incorrect readouts. Reporter assays could be single or dual reporter assays. The reporter could be both luciferases. Most dual-luciferase assays involve adding two reagents to each sample and measuring luminescence following each addition. Adding the first reagent activates the first luciferase reporter reaction; adding the second reagent extinguishes first luciferase reporter activity and initiates the second luciferase reaction. Dual-luciferase assays have some advantages, including 1. reduces variability, 2. reduces background, 3. normalizes differences in transfection efficiencies between samples.

Protein isolation is a technique that involves isolation and/ or purification of protein from cells or tissues via chromatography or electrophoresis. The major challenges in protein isolation include: 1. The concentration of proteins in cells is variable and tends to be small for some intracellular proteins. Unlike nucleic acids, proteins cannot be amplified. 2. Proteins are more unstable than nucleic acids. They are easily denatured under suboptimal temperature, pH or salt concentrations. 3. Finally, no generalized technique/protocol can be applied for protein isolation. Proteins may have different electrostatic (number of positively or negatively charged amino acids) or hydrophobic properties. Therefore, protein purification requires multiple steps depending on their charge (a negatively charged resin/column for positively charged proteins and vice-versa), dissolution (using detergents) and unlike in the case of DNA and RNA, instead of using salts, proteins should be isolated by isoelectric precipitation.

Protein isolation is a technique that involves isolation and/ or purification of protein from cells or tissues via chromatography or electrophoresis. The major challenges in protein isolation include: 1. The concentration of proteins in cells is variable and tends to be small for some intracellular proteins. Unlike nucleic acids, proteins cannot be amplified. 2. Proteins are more unstable than nucleic acids. They are easily denatured under suboptimal temperature, pH or salt concentrations. 3. Finally, no generalized technique/protocol can be applied for protein isolation. Proteins may have different electrostatic (number of positively or negatively charged amino acids) or hydrophobic properties. Therefore, protein purification requires multiple steps depending on their charge (a negatively charged resin/column for positively charged proteins and vice-versa), dissolution (using detergents) and unlike in the case of DNA and RNA, instead of using salts, proteins should be isolated by isoelectric precipitation.

Protein isolation is a technique that involves isolation and/ or purification of protein from cells or tissues via chromatography or electrophoresis. The major challenges in protein isolation include: 1. The concentration of proteins in cells is variable and tends to be small for some intracellular proteins. Unlike nucleic acids, proteins cannot be amplified. 2. Proteins are more unstable than nucleic acids. They are easily denatured under suboptimal temperature, pH or salt concentrations. 3. Finally, no generalized technique/protocol can be applied for protein isolation. Proteins may have different electrostatic (number of positively or negatively charged amino acids) or hydrophobic properties. Therefore, protein purification requires multiple steps depending on their charge (a negatively charged resin/column for positively charged proteins and vice-versa), dissolution (using detergents) and unlike in the case of DNA and RNA, instead of using salts, proteins should be isolated by isoelectric precipitation.

Protein isolation is a technique that involves isolation and/ or purification of protein from cells or tissues via chromatography or electrophoresis. The major challenges in protein isolation include: 1. The concentration of proteins in cells is variable and tends to be small for some intracellular proteins. Unlike nucleic acids, proteins cannot be amplified. 2. Proteins are more unstable than nucleic acids. They are easily denatured under suboptimal temperature, pH or salt concentrations. 3. Finally, no generalized technique/protocol can be applied for protein isolation. Proteins may have different electrostatic (number of positively or negatively charged amino acids) or hydrophobic properties. Therefore, protein purification requires multiple steps depending on their charge (a negatively charged resin/column for positively charged proteins and vice-versa), dissolution (using detergents) and unlike in the case of DNA and RNA, instead of using salts, proteins should be isolated by isoelectric precipitation.

RNA quantification for appropriate concentration and quality (260/280 ratio) is an important step before downstream analysis (including sequencing, RT-qPCR, etc.). Having insufficient RNA quantities or a high salt or phenol in the RNA product can lead to variable or irreproducible downstream results. The various methods used for RNA quantification include: 1. UV spectrophotometric (challenges include: low sensitivity, cannot distinguish between nucleic acid species), 2. Fluorescence-based (challenges include: requires standards, cannot measure amplifiability, not sequence-specific), and 3. RT-PCR (challenges include: requires standards, time-intensive, costly). In order to overcome these challenges, and also to ensure the proper quantification and quality control for RNA product, it is important to use at least two or more methods in order to discard any inconsistencies. Using standards for calibrations increases the sensitivity range for RNA detention (fluorescence- and RT-PCR-based methods). When using RT- PCR, it is important to choose correct primers, aligning to the desired site on the template and of appropriate product length, along with positive, negative and loading controls. It is also important to have at least two primer pairs in order to confirm results.

RNA quantification for appropriate concentration and quality (260/280 ratio) is an important step before downstream analysis (including sequencing, RT-qPCR, etc.). Having insufficient RNA quantities or a high salt or phenol in the RNA product can lead to variable or irreproducible downstream results. The various methods used for RNA quantification include: 1. UV spectrophotometric (challenges include: low sensitivity, cannot distinguish between nucleic acid species), 2. Fluorescence-based (challenges include: requires standards, cannot measure amplifiability, not sequence-specific), and 3. RT-PCR (challenges include: requires standards, time-intensive, costly). In order to overcome these challenges, and also to ensure the proper quantification and quality control for RNA product, it is important to use at least two or more methods in order to discard any inconsistencies. Using standards for calibrations increases the sensitivity range for RNA detention (fluorescence- and RT-PCR-based methods). When using RT- PCR, it is important to choose correct primers, aligning to the desired site on the template and of appropriate product length, along with positive, negative and loading controls. It is also important to have at least two primer pairs in order to confirm results.

RNA quantification for appropriate concentration and quality (260/280 ratio) is an important step before downstream analysis (including sequencing, RT-qPCR, etc.). Having insufficient RNA quantities or a high salt or phenol in the RNA product can lead to variable or irreproducible downstream results. The various methods used for RNA quantification include: 1. UV spectrophotometric (challenges include: low sensitivity, cannot distinguish between nucleic acid species), 2. Fluorescence-based (challenges include: requires standards, cannot measure amplifiability, not sequence-specific), and 3. RT-PCR (challenges include: requires standards, time-intensive, costly). In order to overcome these challenges, and also to ensure the proper quantification and quality control for RNA product, it is important to use at least two or more methods in order to discard any inconsistencies. Using standards for calibrations increases the sensitivity range for RNA detention (fluorescence- and RT-PCR-based methods). When using RT- PCR, it is important to choose correct primers, aligning to the desired site on the template and of appropriate product length, along with positive, negative and loading controls. It is also important to have at least two primer pairs in order to confirm results.

Hello! I used Trizol to extract total RNA from in-vitro cultured bacteria (1 X 10^8 cells). After phase separation, I mixed ~0.4 ml of the upper phase which contains RNA with 0.5 mL cold isopropanol. However, the amount of RNA when measured in Nanodrop was very low. In addition, the ratio between 260 and 230 was around 0.1 to 0.5. Is there a chance that my sample was contaminated by the Trizol reagent? When I collected the aqueous phase I made sure to not touch the lower phase. What should I do?