A combination of mtDNA purification protocols was adopted (Scotti et.al 2001 and Gianniny et.al 2004). Briefly, this method yields 5 µg of mtDNA/g of tomato fresh tissue (etiolated seedlings). Quality control is performed by PCR amplification of serial dilutions of the extracted mtDNA with primers designed on actin (nuclear-), rubisco rbcL (chloroplastic-) and coxII (mitochondrial-specific) genes. mtDNA with less than 10 % of nuclear and chloroplastic contaminations is fragmented by sonication/hydrodynamic and/or enzymatic shearing in a range of 1000-3000 pb and purified from an agarose gel
Purified mtDNA fragments are repaired and ligated into the pMOS-Blue (pMOSBlue Blunt Ended Cloning Kit, Amersham Bioscience) and pZERO-2 vectors (Invitrogen) following the manufacture instructions. Selected clones are classified and stored in freeze media in 96-well plates according the following nomenclature: SlmiNNZZZXY. This code accounts for:
Sl: Solanum lycopersicon LA1706 (seeds provided by the C.M. Rick Tomato Genetics Resource Center, UC Davis).
mi: mitochondrial library
NN: library #
ZZZ: plate #
XY: well place in the plate
Individual clones are free available (only shipping is charge) upon request.
Sequence reads are generated in an ABI 3101 instruments by a single reaction using the M13 forward and reverse primers. Output information is automatically deposited into the INTA01 server. The following pipeline has been designed for information processing:
Base calling by Phred software.
Sequence vector masking by comparison with pMOS-Blue vector sequence using Cross_match with default options.
sequence validation and trimming by SeqClean.
contigs (and singletons) are generated by CAP3 software, with minimum overlap of 40 nt and identity percentage of 90%.
contigs (and singletons) are blasted against the following DB:
- Plant mt seqs (nt)
- Plant mt seqs (translated)
- Other (non plant) mt seqs (nt)
- Other (non plant) mt seqs (translated)
- NCBI nr
- Swissprot
- Out puts are deposited under: INTA01: db1/Mitocondria/Slmi_cat/blast/
- (Threshold E value > 0.001)