- B.Sc., 1982, University of Brasilia (Brasilia, Brazil), Molecular Biology
- M.Sc., 1986, University of Brasilia (Brasilia, Brazil), Molecular Biology
- Ph.D., 1992, University of Georgia, Genetics
- Postdoctoral research, University of Wisconsin, Stanford University, Meiotic silencing.
Joined the dept. 1997
Associations: Faculty of Genetics.
College Station, TX 77843-3258
Biological Sciences Building West
Biological Sciences Building West
|Genetics, Epigenetics and Meiotic RNA Silencing
In my laboratory, we use the filamentous fungus Neurospora crassa, as a model organism to understand meiotic silencing, one of the most amazing and intriguing mechanism observed in meiotic cells of eukaryotic organisms. If a segment of DNA is not present on the opposite homologous chromosome in meiosis in Neurospora, the resulting "unpaired" DNA segment is targeted for silencing. This situation occurs when a DNA element gets inserted at a particular chromosomal position (e.g., a situation akin to the "invasion" of a genome by transposable DNA elements). It can also occur when a normal region gets deleted. In both situations, the resulting loop of "unpaired" DNA activates a genome-wide "alert" system that results in the silencing not only of the genes present in the "unpaired" DNA segment, but also of those same genes if present elsewhere in the genome, even if they are in the paired condition. This phenomenon is called, meiotic silencing and was originally described in Neurospora crassa, but has since been observed in nematodes and mammals. In all these organisms, "unpaired or unsynapsed" regions (or chromosomes) are targeted for gene silencing. We think that meiotic silencing is a two-step process. First meiotic trans-sensing compares the chromosomes from each parent and identifies significant differences as unpaired DNA. Second, if unpaired DNA is identified, a process called meiotic silencing silences expression of genes within the unpaired region and regions sharing sequence identity. We are using a combination of genetics, molecular biology and biochemistry aimed at identifying all the molecular players of the process and at understanding how they work together. Our work is centered on understanding the genetic, molecular, cytogenetic and biochemical characterization of key components of the system: Sms-2, Sms-3, Sms-4, Sms-5, Sms-6, Sms-7, Sms-8, Sms-9, Sms-10 and Sms-11. The long term objective of our work is to understand meiotic silencing in Neurospora and to map its connections with the meiotic silencing observed in other organisms.
- Lee DW, Millimaki R & Aramayo R (2010) QIP, a component of the vegetative RNA silencing pathway, is essential for meiosis and suppresses meiotic silencing in Neurospora crassa. Genetics 186:127-33 Full text
- Lee DW, Freitag M, Selker EU & Aramayo R (2008) A cytosine methyltransferase homologue is essential for sexual development in Aspergillus nidulans. PLoS One 3:e2531 Full text
- Hu JC, Aramayo R, Bolser D, Conway T, Elsik CG, Gribskov M, Kelder T, Kihara D, Knight TF Jr, Pico AR, Siegele DA, Wanner BL & Welch RD (2008) The emerging world of wikis. Science 320:1289-90 Full text
- Vestergaard G, Aramayo R, Basta T, Häring M, Peng X, Brügger K, Chen L, Rachel R, Boisset N, Garrett RA & Prangishvili D (2008) Structure of the acidianus filamentous virus 3 and comparative genomics of related archaeal lipothrixviruses. J Virol 82:371-81 Full text
- Kelly WG & Aramayo R (2007) Meiotic silencing and the epigenetics of sex. Chromosome Res 15:633-51 Full text
- Ng DW, Wang T, Chandrasekharan MB, Aramayo R, Kertbundit S & Hall TC (2007) Plant SET domain-containing proteins: structure, function and regulation. Biochim Biophys Acta 1769:316-29 Full text
- Pratt RJ, Lee DW & Aramayo R (2004) DNA methylation affects meiotic trans-sensing, not meiotic silencing, in Neurospora. Genetics 168:1925-35 Full text
- Bogomolnaya LM, Pathak R, Guo J, Cham R, Aramayo R & Polymenis M (2004) Hym1p affects cell cycle progression in Saccharomyces cerevisiae. Curr Genet 46:183-92 Full text
- Freitag M, Lee DW, Kothe GO, Pratt RJ, Aramayo R & Selker EU (2004) DNA methylation is independent of RNA interference in Neurospora. Science 304:1939 Full text
- Lee DW, Seong KY, Pratt RJ, Baker K & Aramayo R (2004) Properties of unpaired DNA required for efficient silencing in Neurospora crassa. Genetics 167:131-50 Full text