Editing Diatom (section)

=== Genome sequencing ===
[[File:Thalassiosira pseudonana.jpg|thumb|210px| {{center|''[[Thalassiosira pseudonana]]'' was the first eukaryotic marine phytoplankton to  have its genome sequenced}}]]

In 2004, the entire [[genome]] of the centric diatom, ''[[Thalassiosira pseudonana]]'' (32.4 Mb) was sequenced,<ref name="Armbrust 2004">{{cite journal |doi=10.1126/science.1101156 |pmid=15459382 |title=The Genome of the Diatom Thalassiosira Pseudonana: Ecology, Evolution, and Metabolism |journal=Science |volume=306 |issue=5693 |pages=79–86 |year=2004 |last1=Armbrust |first1=E. V. |last2=Berges |first2=John A. |last3=Bowler |first3=Chris |last4=Green |first4=Beverley R. |last5=Martinez |first5=Diego |last6=Putnam |first6=Nicholas H. |last7=Zhou |first7=Shiguo |last8=Allen |first8=Andrew E. |last9=Apt |first9=Kirk E. |last10=Bechner |first10=Michael |last11=Brzezinski |first11=Mark A. |last12=Chaal |first12=Balbir K. |last13=Chiovitti |first13=Anthony |last14=Davis |first14=Aubrey K. |last15=Demarest |first15=Mark S. |last16=Detter |first16=J. Chris |last17=Glavina |first17=Tijana |last18=Goodstein |first18=David |last19=Hadi |first19=Masood Z. |last20=Hellsten |first20=Uffe |last21=Hildebrand |first21=Mark |last22=Jenkins |first22=Bethany D. |last23=Jurka |first23=Jerzy |last24=Kapitonov |first24=Vladimir V. |last25=Kröger |first25=Nils |last26=Lau |first26=Winnie W. Y. |last27=Lane |first27=Todd W. |last28=Larimer |first28=Frank W. |last29=Lippmeier |first29=J. Casey |last30=Lucas |first30=Susan | display-authors = 6 | bibcode=2004Sci...306...79A |citeseerx=10.1.1.690.4884 |s2cid=8593895 }}</ref> followed in 2008 with the sequencing of the pennate diatom, ''[[Phaeodactylum tricornutum]]'' (27.4 Mb).<ref name="Bowler 2008">{{cite journal |doi=10.1038/nature07410 |pmid=18923393 |title=The Phaeodactylum genome reveals the evolutionary history of diatom genomes |journal=Nature |volume=456 |issue=7219 |pages=239–244 |year=2008 |last1=Bowler |first1=Chris |last2=Allen |first2=Andrew E. |last3=Badger |first3=Jonathan H. |last4=Grimwood |first4=Jane |last5=Jabbari |first5=Kamel |last6=Kuo |first6=Alan |last7=Maheswari |first7=Uma |last8=Martens |first8=Cindy |last9=Maumus |first9=Florian |last10=Otillar |first10=Robert P. |last11=Rayko |first11=Edda |last12=Salamov |first12=Asaf |last13=Vandepoele |first13=Klaas |last14=Beszteri |first14=Bank |last15=Gruber |first15=Ansgar |last16=Heijde |first16=Marc |last17=Katinka |first17=Michael |last18=Mock |first18=Thomas |last19=Valentin |first19=Klaus |last20=Verret |first20=Fréderic |last21=Berges |first21=John A. |last22=Brownlee |first22=Colin |last23=Cadoret |first23=Jean-Paul |last24=Chiovitti |first24=Anthony |last25=Choi |first25=Chang Jae |last26=Coesel |first26=Sacha |last27=De Martino |first27=Alessandra |last28=Detter |first28=J. Chris |last29=Durkin |first29=Colleen |last30=Falciatore |first30=Angela |display-authors = 6 | bibcode=2008Natur.456..239B |s2cid=4415177 |doi-access=free }}</ref> Comparisons of the two reveal that the ''P. tricornutum'' genome includes fewer genes (10,402 opposed to 11,776) than ''T. pseudonana''; no major synteny (gene order) could be detected between the two genomes. ''T. pseudonana'' genes show an average of ~1.52 introns per gene as opposed to 0.79 in ''P. tricornutum'', suggesting recent widespread intron gain in the centric diatom.<ref name="Bowler 2008" /><ref>{{cite journal |doi=10.1093/molbev/msm048 |pmid=17350938 |title=A Very High Fraction of Unique Intron Positions in the Intron-Rich Diatom Thalassiosira pseudonana Indicates Widespread Intron Gain |journal=Molecular Biology and Evolution |volume=24 |issue=7 |pages=1447–57 |year=2007 |last1=Roy |first1=S. W. |last2=Penny |first2=D. |doi-access=free }}</ref> Despite relatively recent evolutionary divergence (90 million years), the extent of molecular divergence between centrics and pennates indicates rapid evolutionary rates within the [[Bacillariophyceae]] compared to other [[eukaryotic]] groups.<ref name="Bowler 2008" /> [[Comparative genomics]] also established that a specific class of [[transposable elements]], the Diatom Copia-like retrotransposons (or CoDis), has been significantly amplified in the ''P. tricornutum'' genome with respect to ''T. pseudonana'', constituting 5.8 and 1% of the respective genomes.<ref name="Maumus etal 2009">{{cite journal |doi=10.1186/1471-2164-10-624 |pmid=20028555 |pmc=2806351 |title=Potential impact of stress activated retrotransposons on genome evolution in a marine diatom |journal=BMC Genomics |volume=10 |pages=624 |year=2009 |last1=Maumus |first1=Florian |last2=Allen |first2=Andrew E |last3=Mhiri |first3=Corinne |last4=Hu |first4=Hanhua |last5=Jabbari |first5=Kamel |last6=Vardi |first6=Assaf |last7=Grandbastien |first7=Marie-Angèle |last8=Bowler |first8=Chris |doi-access=free }}</ref>