Non-symmetrical cytosine methylation in tobacco pollen DNA

✍ Scribed by Edward J. Oakeley; Jean-Pierre Jost

• Book ID: 104615383
• Publisher: Springer
• Year: 1996
• Tongue: English
• Weight: 505 KB
• Volume: 31
• Category: Article
• ISSN: 0167-4412
• DOI: 10.1007/bf00019481

✦ Synopsis

We have detected sequence-specific non-symmetrical cytosine methylation within a 140 bp region of the promoter for the tobacco auxin-binding protein gene T85 in pollen DNA. Direct sequencing of the population of bisulphite reaction products showed that, in this region. 10 out of a possible 49 cytosine residues were methylated at a high frequency in pollen whereas the corresponding region from somatic cells (leaf DNA) did not show a detectable level of methylation. The context of these sites was 1 x m5CpTpC, 1 x m5CpGpT, 1 x m5CpCpT, 2 x m5CpTpT, 2 x m5CpGpG, and 3 x m5CpApT of which only m5CpGpG and m5CpGpT fitted the consensus sequence for symmetrical methylation in plants.