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  • Simonli
    Member
    • Oct 2013
    • 14

    Trinity can not recognize the reads

    Well, this is basically a followup from here (http://seqanswers.com/forums/showthread.php?t=34703): I first use *.fasta to feed trinity, it shows my reads could not be deciphered as being /1 or /2 of a PE fragment.
    and my fasta files was like:

    >HISEQ:190:C2L5LACXX:7:1101:2055:1989 1:N:0:ATCATG
    AACAATTTCATCCTCGAATCCTACCACACGGGCGCTGGCACCGCCTACGCCGTCCTCGCTGAGAACACCACCGAAGCCAACCCTCGCACCTTCTACGTGA
    >HISEQ:190:C2L5LACXX:7:1101:3448:1999 1:N:0:ATCACG
    GTCGTATGCAAAGGATTCAACCCCACGCATTGTAAAATTGCAAGACGCCAGTTAGTCCTAAAGAGTTTCTTCAATAGGACCGTTACCAGCCAGCTAAGAT
    >HISEQ:190:C2L5LACXX:7:1101:3524:1986 1:N:0:ATCACG
    CTTGTCCTTCTTCTCTTTCCTCTCTTTGGTTTTATCTGACACAAGATCCTTCTCAATCTTATCGAGACTCGGCCTCTGCTTGAGTTTCTCAGAGTCATTA
    >HISEQ:190:C2L5LACXX:7:1101:4204:1996 1:N:0:ATCACG
    GTGTTAAAAGGGCTAGAGATCGAAATGTTAGACAAAGCGAAATGGAGCAAAGACTGGCAGATCCCAACCAATCCCAATCACGCCGAGAACAAACTTGGTC
    >HISEQ:190:C2L5LACXX:7:1101:4587:2000 1:N:0:ATCACG
    Then I wrote a script (hope this would help somebody has the same problem) to add /1 or /2 to the fasta files:

    f = open("merged1.fasta")
    output = open("1.fasta",'w')
    i = 1
    for line in f:
    if (i % 2) > 0:
    str = line.split()
    output.write(str[0]+' ')
    output.write(str[1][2:]+"/1\n")
    else:
    output.write(line)
    i = i+1
    Then the fasta files turn to:

    >HISEQ:190:C2L5LACXX:7:1101:2055:1989 N:0:ATCATG/1
    AACAATTTCATCCTCGAATCCTACCACACGGGCGCTGGCACCGCCTACGCCGTCCTCGCTGAGAACACCACCGAAGCCAACCCTCGCACCTTCTACGTGA
    >HISEQ:190:C2L5LACXX:7:1101:3448:1999 N:0:ATCACG/1
    GTCGTATGCAAAGGATTCAACCCCACGCATTGTAAAATTGCAAGACGCCAGTTAGTCCTAAAGAGTTTCTTCAATAGGACCGTTACCAGCCAGCTAAGAT
    >HISEQ:190:C2L5LACXX:7:1101:3524:1986 N:0:ATCACG/1
    CTTGTCCTTCTTCTCTTTCCTCTCTTTGGTTTTATCTGACACAAGATCCTTCTCAATCTTATCGAGACTCGGCCTCTGCTTGAGTTTCTCAGAGTCATTA
    >HISEQ:190:C2L5LACXX:7:1101:4204:1996 N:0:ATCACG/1
    GTGTTAAAAGGGCTAGAGATCGAAATGTTAGACAAAGCGAAATGGAGCAAAGACTGGCAGATCCCAACCAATCCCAATCACGCCGAGAACAAACTTGGTC
    >HISEQ:190:C2L5LACXX:7:1101:4587:2000 N:0:ATCACG/1
    Then I feed these reads to run Trinity again(I use seperate 4 stages), the first stage(inchworm) was good, however in the 2nd stage,

    The error report showing:

    Use of uninitialized value $pm_temp in division (/) at /local_scratch/.../Trinity.pl line 887
    Use of uninitialized value $pm_temp in division (/) at /local_scratch/.../Trinity.pl line 890
    So it seems manually rename the reads doesn`t work...

    Anybody any ideas can figure that out?

    Simon
  • Simonli
    Member
    • Oct 2013
    • 14

    #2
    correction, the second trial changed the python script a little bit and the output heading is like this:
    >HISEQ:190:C2L5LACXX:7:1101:2055:1989/1
    AACAATTTCATCCTCGAATCCTACCACACGGGCGCTGGCACCGCCTACGCCGTCCTCGCTGAGAACACCACCGAAGCCAACCCTCGCACCTTCTACGTGA
    I`ll see if it works.

    Comment

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