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Cloning and Sequencing Explorer Series

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Title: Cloning and Sequencing Explorer Series


1
(No Transcript)
2
Cloning and Sequencing Explorer
Series Bioinformatics
3
Instructors
  • Stan Hitomi
  • Coordinator Math Science
  • Principal Alamo School
  • San Ramon Valley Unified School District
  • Danville, CA
  • Kirk Brown
  • Lead Instructor, Edward Teller Education Center
  • Science Chair, Tracy High School
  • and Delta College, Tracy, CA
  • Bio-Rad Curriculum and Training Specialists
  • Sherri Andrews, Ph.D.
  • sherri_andrews_at_bio-rad.com
  • Essy Levy, M.Sc.
  • essy_levy_at_bio-rad.com
  • Leigh Brown, M.A.

4
Bioinformatics
  • The application of information technology to
    molecular biology

5
Questions Concerning your Data
  • Class Data Set
  • Are our sequences high quality?
  • Are my sequences similar to GAPDH?
  • Are any of my sequences primarily cloning vector?
  • Individual Clone Sequences
  • Do my individual sequences align to give me a
    single long sequence?
  • Are there discrepancies between my reads?
  • Which GAPDH gene did we clone?
  • Annotation of Clone Sequence
  • What is the intron- exon structure/mRNA sequence
    of my clone?
  • What is the protein sequence of my clone?

6
Sequence data storage and analysis tools (iFinch
and Finch TV) Sequence comparison algorithm (NCBI
BLAST) Sequence Assembly (CAP3) mRNA sequence
prediction (BLAST and manual) Protein sequence
prediction (EMBL-EBI EMBOSS Transeq)
Sequence Data Analysis Tools
7
Advanced Preparation
  • Practice with iFinch using the guest account-
    highly recommended!
  • Activate your iFinch account (2 months
    subscription)
  • Download FinchTV onto lab computers
  • Set up project and folder in iFinch
  • Upload sequence data

8
Guest iFinch Account
  • http//classroom1.bio-rad.ifinch.com/Finch
  • Username BR_guest
  • Password guest
  • Example data sets for each stage of process
  • No uploading of data

9
Your own iFinch account
  • Each account has a unique URL
  • http//Platenumber.ifinch.com/Finch
  • E.g. http//A150936.ifinch.com/Finch
  • Instructors Username Platenumber e.g. A150936
  • Instructors Password Platenumber e.g. A150936
  • Student Username Platenumber_student e.g.
    A150936_student
  • Student Password Platenumber e.g. A150936
  • Once activated- change your passwords!
  • Active for 2 months.

10
Download FinchTV
  • www.geospiza.com/finchtv

11
Make project folder and upload data to
iFinchDemo
12
Student Activities
  1. Review data quality and view sequence traces
  2. Use BLAST for preliminary check on which GAPDH
    was cloned
  3. Assemble sequences into a contig
  4. Verify which GAPDH gene was cloned
  5. Predict intron exon boundaries and generate mRNA
    sequence
  6. Predict protein sequence

13
Sequence Quality
14
Q20 values
  • The quality value of a base call is
  • Q -10Log10(Perror)
  • where P is the probability of an error.
  • Thus if the chance that a base call is incorrect
    is 1/100, P would be 0.01 and the quality value
    would be 20 (Q20).
  • Convention rates sequences by the number of
    basecalls that have quality values of 20 or
    higher- a Q20 value.
  • The quality values of a sequence are calculated
    automatically by software in iFinch- a common
    program for this was developed by the University
    of Washington and is called Phred

15
Sequence Quality
Q20 732
Q20 161
Q20 238
16
iFinch and Sequence Quality
17
Screen for poor quality sequence, vector, GAPDH
family
18
Class Data Set
19
Sort Class Data into Folders
20
Record Data Information
21
Download sequences for initial screen using BLAST
  • Open Guest iFinch account
  • User BR-guest, Psw guest
  • Click Folders
  • Click Salvia folder
  • Look at data
  • Go back to folder report
  • Click Download folder data- save to new folder
    on hard drive
  • View FASTA format in MSWord or text editor
  • Upload file back to iFinch

22
BLAST sequences for initial screen
  • Click NCBI BLAST on iFinch homepage
  • Choose nucleotide search
  • Browse for downloaded salvia.fsa file to upload
  • Choose Others (nr etc), Select Reference
    Genomic sequences
  • Choose Plants (taxid)
  • Choose Somewhat similar sequences (blastn)
  • Click BLAST

23
BLAST Results
  • All 4 sequences were analyzed by BLAST- choose
    from pull down menu at top of page
  • Mouse over top bar
  • Scroll down to list of homologous sequences
  • E value represents the number of equally good
    sequence matches to the query sequence that would
    be expected in a database of the same size
    containing random sequences.
  • Scroll down to sequence alignments
  • Query Your sequence
  • Subject Database matching sequence

24
Which GAPC Gene?
25
  • Break time!

26
Questions Concerning your Data
  • Class Data Set
  • Are our sequences high quality?
  • Are my sequences similar to GAPDH?
  • Are any of my sequences primarily cloning vector?
  • Individual Clone Sequences
  • Do my individual sequences align to give me a
    single long sequence?
  • Are there discrepancies between my reads?
  • Which GAPDH gene did we clone?
  • Annotation of Clone Sequence
  • What is the intron- exon structure/mRNA sequence
    of my clone?
  • What is the protein sequence of my clone?

27
Initial Screen Result
  • We have cloned Salvia GAPC gene
  • Now we need to put the sequences together to make
    a contig- (contiguous sequence)
  • Then correct any sequence discrepancies between
    different reads

28
CAP3 Program(ContigAssemblyProgram)
  • On iFinch home page click sequence assembly

29
Assembly Results
  • Your sequence file (your input)
  • Single sequences (any seqs that could not be
    assembled)
  • Contigs (save in FASTA format as .txt file)
  • Assembly details (Save as landscape .txt file)

30
Salvia Contig
A01
I01
C01
G01
31
Check for Discrepancies
  • Look through assembly file for sequence
    discrepancies
  • Open chromatogram files in FinchTV
  • Examine actual chromatograms and use personal
    judgment to determine which base call is correct
  • Correct FinchTV file and save back to iFinch (not
    available in guest account) noting the changes in
    the revision history
  • If the consensus sequence has changed, download
    folder sequences again like previously and
    reassemble with CAP3 program

32
BLAST search with contig
Submit contig FASTA file for BLAST search (same
database as before- plant reference genomic
database)
33
  • Break time!

34
Questions Concerning your Data
  • Class Data Set
  • Are our sequences high quality?
  • Are my sequences similar to GAPDH?
  • Are any of my sequences primarily cloning vector?
  • Individual Clone Sequences
  • Do my individual sequences align to give me a
    single long sequence?
  • Are there discrepancies between my reads?
  • Which GAPDH gene did we clone?
  • Annotation of Clone Sequence
  • What is the intron- exon structure/mRNA sequence
    of my clone?
  • What is the protein sequence of my clone?

35
Determine Gene Structure
36
Workflow
37
BLAST Search Against Reference mRNA Database
  • Blastn search with contig against plant Reference
    mRNA sequences database
  • Change Algorithm parameters

38
Reformat BLAST results
  • Reformat results in plain text format
  • Save files to iFinch folder

39
Save Contig File in MSWord
  • Delete all paragraph marks using find and replace
    command
  • Save to hard drive as .rtf file with a new
    name.
  • Color contig sequence with exons as determined
    from BLAST results
  • Put exons together in a first draft of the mRNA
    sequence and save to iFinch folder
  • Submit draft mRNA sequence to blastn against
    plant reference mRNA database

40
BLAST search with derived mRNA sequence
  • Correct intron-exon boundaries (use Arabidopsis
    mRNA as model)
  • Resubmit to BLAST
  • Reiterate if necessary until no indels are
    evident and you are satisfied with a final mRNA
    sequence
  • Save to iFinch folder

41
Use blastx to Search Protein Database
  • Blastx converts nucleic acid sequence to amino
    acid sequence and searches protein database.

42
Translate mRNA into Protein Sequence
43
Check Protein Sequence with blastp Search
  • Ensure translation is in correct frame
  • Save to iFinch folder

44
Congratulations!
  • You have cloned, sequenced and annotated a novel
    gene.
  • You could now submit this to GenBank.
  • Data from additional samples would strengthen the
    data- for example- assemble sequences from the
    same gene from different student teams
  • Download data from iFinch if you wish to keep it
    for the long term

45
Webinars
  • Enzyme Kinetics A Biofuels Case Study
  • Real-Time PCR What You Need To Know and Why You
    Should Teach It!
  • Proteins Where DNA Takes on Form and Function
  • From plants to sequence a six week college
    biology lab course
  • From singleplex to multiplex making the most out
    of your realtime experiments
  • explorer.bio-rad.com?Support?Webinars
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