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June 9th, 2008 | Viewed 703 times, 1 so far today | 1 Comment

After I sign in, the SmartNote Notebook page does not load. I use Windows Internet Explorer 7 on a machine running Windows XP (SP2). The status bar at the bottom of the page shows ‘error on page.’ I am also unable to load the feedback page. Has anyone come across this? How to fix this?

DNASIS SmartNote Gets Graphical, xTAG Improved

June 4th, 2008 | Viewed 662 times, 1 so far today | 0 Comments

1. DNASIS SmartNote now shows a graphical view of any sequence annotations included in files imported from Entrez. To see it, click the “Details” link next to the sequence in the “My Sequences” view. Here’s what it looks like:



2. The xTAG Tool now lets you exclude certain bead regions. In addition, its results now also include tag and anti-tag sequences.

Introduction to NCBI BLAST

May 28th, 2008 | Viewed 1944 times | 0 Comments

NCBI BLAST, the Basic Local Alignment Search Tool (BLAST) is a suite of programs designed to search all available sequence databases for similarities between a protein or DNA query and known sequences. BLAST allows quick matching of near and distant sequence relationships, providing scores that allow the user to distinguish real matches from background hits with a high degree of statistical accuracy.

Focusing on local alignments, BLAST uses a heuristic algorithm to detect relationships between sequences that may only share isolated regions of similarity. BLAST results take sequence length and the nucleotide/peptide compositions of the query into account when assigning alignment scores. For sequences shorter than 200 residues, an effective length is used to compensate for “edge effects”. Sequence alignment scores are reported by BLAST programs as E-values that reflect the strength of alignment between a given sequence in the database and a query. E-values are reported instead of the traditional P-value, to improve resolution between low scoring alignments, but for closely related sequences (P < 0.01), these values are nearly equal.

For more detailed information on how BLAST scores are calculated, visit:

http://www.ncbi.nlm.nih.gov/BLAST/tutorial/Altschul-1.html

For most first-time users of BLAST, choosing the right sub-program may be difficult. BLAST offers a variety of search tools for different types of queries. In general, the best choice of program depends upon the sequence length, the database being searched, and the information requested in the search.

Nucleotide BLAST is a collection of programs allowing users to compare a query sequence against other nucleotides in the database. BLAST accepts sequences in a variety of formats, including FASTA, GenBank, and Accession/GI numbers, and compares these with the NCBI databases. MEGABLAST is a concatenating algorithm for quickly aligning sequences longer than 28 residues. For shorter sequences, such as primers, standard nucleotide-nucleotide BLAST offers automatic parameter settings suited to these queries.

Protein BLAST is a collection of programs used to find protein sequences similar to a query. These programs accept sequences in the same file formats as Nucleotide BLAST. PSI-BLAST is a position specific, iterating algorithm that searches sequences from each round as the basis for scoring sequences searched in the next round. It distinguishes between highly and weakly conserved positions in the sequence, resulting in increased sensitivity with each iteration. PSI BLAST also offers the option of including regular expression patterns in the search, allowing users to identify sequences that include a pattern and are homologous to the query protein sequence. As with Nucleotide BLAST, Protein BLAST includes automatic parameter settings for shorter sequences.

Translating BLAST operates in a similar fashion to both the nucleotide and protein search routines. BLASTX translates nucleotide sequences into protein sequences in each of the 6 reading frames, prior to comparing the query to the protein databases. TBLASTN compares a protein sequence query against a database of nucleotide sequences previously translated in each of the 6 reading frames.

Users can refer to the NCBI BLAST program selection guide for more information:
http://www.ncbi.nlm.nih.gov/blast/producttable.shtml
.

Users can access BLAST tools directly through the web, or through a variety of software applications, such as MiraiBio’s DNASIS SmartNote, which helps users find and organize sequences, and automatically submit them to the BLAST programs. DNASIS SmartNote has the additional ability to BLAST multiple sequences “in batch” without tediously copying/pasting each sequence and waiting for each result to come back.

To learn more about DNASIS SmartNote, visit http://smartnote.miraibio.com.

Better Sequence Importing and Exporting

May 22nd, 2008 | Viewed 648 times | 0 Comments

We have 3 improvements to report for DNASIS SmartNote this week, all having to do with more efficient sequence importing and exporting:

1. Accession number recognition - DNASIS SmartNote now recognizes accession numbers in sequences you import (or will ask you to enter one if you paste in a raw sequence). This gives you better control over the naming of your sequences, so you can keep better track of which results belong to which sequence.

2. Import multiple sequences at once - If you’d like to import several sequences into DNASIS SmartNote and you know their accession numbers, you can now enter them all (separated by commas). To try it out, click on “Get Sequences” under DNASIS SmartNote’s “Sequences” tab, then select “Search for sequences from NCBI Entrez” or “Search for SNPs from NCBI DB”

3. Export raw results from xTAG Software tool - For those who are using DNASIS SmartNote’s new tools for designing tagged, gene-specific oligos (GSO) for their Luminex assays using Universal Array beads, the xTAG tool can now export results as comma-separated values (CSV), so you can transfer the data to Microsoft Excel or other spreadsheet programs. The output fields are: “Sequence Name”, “Bead Region” and “Oligo Sequence”

ASPE Assay Design tool and xTAG Software tool now available in DNASIS SmartNote

May 14th, 2008 | Viewed 948 times, 3 so far today | 0 Comments

From MiraiBio’s blog:

Hitachi Software’s MiraiBio Group has recently launched 2 new software tools in the DNASIS SmartNote web application: the Allele Specific Primer Extension (ASPE) Assay Design tool and the xTAG Software (formerly TagIT) tool. These tools are important time savers for those who are interested in multiplexing their SNP or genotyping assays on the Luminex xMAP (also sold by Bio-Rad as the Bio-Plex) platform.

The ASPE Assay Design tool designs probes and primers by optimizing melting temperatures and screening for cross reactivity among the probe and primer sets. All you have to do is to provide the tool with your sequences, SNP position, and allele variants (if you have the SNP rs accession number this information will automatically be populated ). You will get a comprehensive report on the amplification primer pairs that are recommended along with the tagged allele specific primers and the corresponding MicroPlex xTAG Microspheres (formerly FlexMAP beads) to use in your assay. You will even be able to purchase the Microspheres directly from Hitachi Software! It doesn’t get any easier than this.

If you have already designed your allele specific primers, then you have the option of using the xTAG Software tool to select the right MicroPlex xTAG Microspheres to use in your assay.

DNASIS SmartNote
is a free web application that is an in silico lab notebook for molecular biologists. Use it to:
• Analyze sequences with dozens of tools
• Access and edit your notebook from anywhere
• Share sequences and results with friends
• Publish results to a blog

Try it out!

QUEARY FOR RPA

May 3rd, 2008 | Viewed 612 times | 0 Comments

i am a research student , working in fingerprinting project; for complition of my work i need Ribonuclease protection assay(RPA). I want to know is any one have IDIA here about this and specially for probe development for this purpose??
if any one here know this technique or have somthing helpful idia please contact me in my e mail
chimerajit@gmail.com

DNASIS SmartNote Gets More Social (and now imports SNPs)

April 30th, 2008 | Viewed 624 times, 1 so far today | 0 Comments

We’ve added a new “Friends” tab to make it easier to invite friends and colleagues to use DNASIS SmartNote. There are two options:

1 - Invite Friends - This is just an easy way to tell your friends and colleagues about DNASIS SmartNote, because every molecular biologist should be using it. :-)

2 - Invite and Share Notebook with Friends - This lets you not just invite friends to get their own account, but also to share their notebook and sequences with you. If they agree, you’ll be able to collaborate in cool new ways. First, you’ll be able to see read-only views of each other’s notebooks, which will appear below your own notebook navigator in DNASIS SmartNote’s left pane. Second, you’ll also be able to easily view or import each other’s sequences. You can then run your own analyses on your friend’s sequences. How cool is that?

On a separate “note”, we’ve added a new option under the “Sequences” tab for importing SNP sequences from NCBI. You can either search by keyword or by accession number. Enjoy!

Several Improvements to DNASIS SmartNote This Week

March 31st, 2008 | Viewed 729 times, 1 so far today | 0 Comments

1. A job queuing system was implemented - You no longer need to wait for compute-intensive results (e.g. BLAST searches on multiple sequences) to come back. Just submit a job and continue working. When the results are in, you’ll be notified.

2. You can now add comments to tools and read other users’ comments. See what your colleagues have to say about which tools are best for a given task, or if there’s any tips and tricks to get the most value from a tool.

3. Auto-scrolling to results has been fixed - When you click on a result in the left pane, the right pane will automatically scroll to the corresponding position on the page so you can instantly access any result.

4. More help features to guide new users - You’ll notice several new icons to help you use SmartNote’s features.

5. Other cool additions such as the new animated progress icon for the sequence manager window.

6. Many bug fixes - everything just works more smoothly.

Remember to tell us what you think about DNASIS SmartNote and what new features you’d like to see. We’ve been making changes weekly, so as long as your request is reasonable, we’ll most likely be able to add it.

Tracking Articles Related to Your Sequences

March 13th, 2008 | Viewed 883 times | 0 Comments

By default, DNASIS SmartNote will track PubMed articles related to up to 10 of your most recently imported sequences. You can view these regularly updated articles by clicking on the “Articles” tab. From here, you can also clip individual articles into your notebook, as well as print and email them.

If you want to receive regular email updates for new articles, you’ll need to explicitly mark at least one of your sequences listed in the “My Seq’s” tab. You will then start receiving regular emails with any newly published articles related to your sequences. Since you can only track 10 sequences, the sequences you have explicitly marked will get higher priority.

How does DNASIS SmartNote find related articles? If the sequence was imported as a GenBank file, DNASIS SmartNote looks for gene names in the annotations. Otherwise, it defaults to a plain text search of words in the sequence’s description.

We invite you to try out this new feature and let us know if we can do anything to improve it for you.

10 Tips For Designing PCR Primers That Work

March 3rd, 2008 | Viewed 11106 times, 1 so far today | 0 Comments

Since PCR primer design is one of the most widely used features of DNASIS SmartNote, we did some research and put together a list of the top 10 tips for designing PCR primers that work. When designing oligonucleotide primers for PCR, it is helpful to keep some considerations in mind to optimize the output and specificity of your experiment. Here are some tips gathered from experts to get you started:

1. Design your PCR primers to be 18-30 oligo nucleotides in length. The longer end of this range allows higher specificity and gives you space to add restriction enzyme sites to the primer end for cloning.

2. Make sure the melting temperature (Tm) of the primers used are not more than 5°C different from each other. You can calculate Tm with this formula: Tm = 4(G + C) + 2(A + T)°C

3. Aim for a Tm between 65 and 70°C for each primer over the region of hybridization

4. Use an annealing temperature (Ta) of 10 to 15°C lower than the Tm.

5. The GC content of each primer should be in the range of 40-60% for optimum PCR efficiency.

6. Try to have uniform distribution of G and C nucleotides, as clusters of G’s or C’s can cause non-specific priming.

7. Avoid long runs of the same nucleotide.

8. Check that primers are not self-complementary or complementary to the other primer in the reaction mixture, as this will encourage formation of hairpins and primer dimers and will compete with the template for the use of primer and reagent.

9. If you can, make the 3′ end terminate in C or A, as the 3′ is the end which extends and neither the C or A nucleotide wobbles. This will increases the specificity.

10. You can avoid mispriming by making the 3′ end slightly AT rich.

11. Use the right software. OK, so it’s 11 tips. Using the right software is a great way to automate these steps and minimize errors, especially when you have to design primers for many sequences. DNASIS SmartNote includes several primer design tools and is also a lab notebook that automatically keeps a record of your analysis results. You should definitely give it a try. Click here to sign up a free account.

References:
http://rothlab.ucdavis.edu/protocols/PrimerDesign.html
http://www.biochem.ucl.ac.uk/bsm/nmr/protocols/protocols/oligo.html
http://www.protocol-online.org/prot/Molecular_Biology/PCR/PCR_Primer/
http://www.mcb.uct.ac.za//pcroptim.htm