Albert Erives

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Albert Erives
(Adalberto Jorge Erives)
Born (1972-03-04)March 4, 1972
San Fernando, CA, USA
Residence Iowa City, Iowa, USA
Citizenship  United States
Nationality American
Fields Biology
Institutions University of Iowa, Dartmouth College
Alma mater California Institute of Technology, University of California, Berkeley
Doctoral advisor Michael Levine
Known for gene regulation, molecular evolution, genomics
Notable awards NSF CAREER award

Albert Erives (born March 4, 1972) is a biologist, who proposed the pacRNA model for the joint origin of the genetic code and universal homochirality.[1] He is known for work at the intersection of genetics, evolution, developmental biology, and gene regulation.[2][3][4][5] He has worked at the California Institute of Technology, University of California, Berkeley, and Dartmouth College, and is a professor at the University of Iowa.

Molecular determinants of the genetic code[edit]

Inspired by results from Archaea genomics, Erives elaborated and described a specific stereochemical model of proto-anti-codon RNAs (pacRNAs).[1] The pacRNA model appears to predict the genetic code (i.e. the codon table) and biogenic amino acids. In addition, Erives uses the pacRNA model to show that the origin of the genetic code is related to another fundamental unsolved problems in biology: the evolutionary origins of universal homochirality. The model strongly implies that early RNA world was immediately an aminoacylated RNA world and that proteinogenic amino acids arose because of this intrinsic relation between nucleotides and a limited set of "biogenic" amino acids. The pacRNA model explicitly lists possible interactions between various anti-codon di-nucleotide and tri-nucleotide sequences and specific amino acids. When the nucleotides are D-ribose based, L-amino acids are preferred. The pacRNA model may also explain why extant tRNAs are heavily modified in all three domains of life.

Erives first presented the pacRNA model at NASAs 2012 Astrobiology Science Conference[6] and most recently at the 2013 Iowa City Darwin Day festival,[7] which focused on the origins of life on Earth.

Molecular determinants of responses to a morphogen[edit]

Erives and colleagues determined how different morphogen gradient responses are encoded in DNA sequence.[2][5] They did so by using diverse Drosophila species that have different sized eggs to study how a set of structured enhancers[4][8] would have co-evolved or co-adapted to changes in the concentration gradients. Morphogen gradient systems are a core fundamental subject of developmental biology. Models of how morphogen gradient responses were encoded had previously been proposed but had not been tested at the genomic level nor across a set of functionally related enhancers.

Two major unexpected findings resulted from this work. The first result showed that different gradient responses were not encoded in transcription factor (TF) binding site quality or quantity (site density) as expected, but rather were encoded in the precise spacing between binding sites for the morphogen TF and its partner TF.[2] The second result was necessary for arriving at the first result and showed that homotypic site clustering at the enhancers was a result of complex evolutionary history of selection for different threshold responses in the evolving insect egg rather than evidence of complex binding sites with unknown molecular functions.[5]

Ciona[edit]

With his doctoral advisor Michael Levine, Erives authored several papers on ascidian developmental biology, with key insights into the evolution of the proto-vertebrate body plan. [9] [10] [11] [12]

References[edit]

  1. ^ a b Erives A (2011). "A Model of Proto-Anti-Codon RNA Enzymes Requiring L-Amino Acid Homochirality". J Molecular Evolution 73: 10–22. doi:10.1007/s00239-011-9453-4. PMC 3223571. PMID 21779963. 
  2. ^ a b c Crocker, J., Tamori, Y. and Erives, A. (2008). "Evolution acts on enhancer organization to fine-tune gradient threshold readouts". PLoS Biology. 6:e263. doi:10.1371/journal.pbio.0060263. PMC 2577699. PMID 18986212. 
  3. ^ Brown, S., Cole, M. and Erives, A.J. (2008). "Evolution of the holozoan ribosome biogenesis regulon". BMC Genomics. 9:442. doi:10.1186/1471-2164-9-442. PMC 2570694. PMID 18816399. 
  4. ^ a b Erives, A. (2009). "Non-homologous structured CRMs from the Ciona genome". J Comp Biology 16 (2): 369–377. doi:10.1089/cmb.2008.20TT. PMID 19193153. 
  5. ^ a b c Crocker, J., Potter, N. and Erives, A. (2010). "Dynamic evolution of precise regulatory encodings creates the clustered site signature of enhancers". Nature Communications 1:99 (7): 99. doi:10.1038/ncomms1102. PMC 2963808. PMID 20981027. 
  6. ^ 2012 Astrobiology Science Conference. url: http://abscicon2012.arc.nasa.gov/
  7. ^ 2013 Iowa City Darwin Day. url: http://icdarwin.org
  8. ^ Erives, A. and Levine, M. (2004). "Coordinate enhancers share common organizational featuresin the Drosophila genome". Proc Natl Acad Sci U S A 101 (11): 3851–3856. doi:10.1073/pnas.0400611101. PMC 374333. PMID 15026577. 
  9. ^ Erives, A., Levine, M. (2001). "Cis-regulation of ascidian tail muscle genes.". Proceedings of the First International Symposium on the Biology of Ascidians. Springer-Verlag, Tokyo 2001. 
  10. ^ Erives, A. and Levine, M. (2000). "Characterization of a maternal T-box gene in Ciona intestinalis.". Developmental Biology 225: 169–178. doi:10.1006/dbio.2000.9815. 
  11. ^ Erives, A., Corbo, J.C., Levine, M. (1988). "Lineage-specific regulation of the Ciona snail gene in the embryonic mesoderm and neuroectoderm.". Developmental Biology 194: 213–225. 
  12. ^ Takahashi, H., Hotta, K., Erives, A., Di Gregorio, A., Zeller, R.W., Levine, M. and Satoh, N. (1999). "Brachyury downstream notochord differentiation in the ascidian embryo.". Genes & Development 13: 1519–1523. doi:10.1101/gad.13.12.1519. 

External links[edit]