Bottjer David J, Davidson Eric H, Peterson Kevin J, Cameron R Andrew
Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089-0740, USA.
Science. 2006 Nov 10;314(5801):956-60. doi: 10.1126/science.1132310.
Paleogenomics propels the meaning of genomic studies back through hundreds of millions of years of deep time. Now that the genome of the echinoid Strongylocentrotus purpuratus is sequenced, the operation of its genes can be interpreted in light of the well-understood echinoderm fossil record. Characters that first appear in Early Cambrian forms are still characteristic of echinoderms today. Key genes for one of these characters, the biomineralized tissue stereom, can be identified in the S. purpuratus genome and are likely to be the same genes that were involved with stereom formation in the earliest echinoderms some 520 million years ago.
古基因组学将基因组研究的意义追溯到数亿年前的漫长时间。既然海胆紫球海胆的基因组已被测序，那么就可以根据人们熟知的棘皮动物化石记录来解读其基因的运作。最早出现在寒武纪早期形态中的特征在如今的棘皮动物中仍然具有代表性。其中一个特征——生物矿化组织立体骨针的关键基因，可以在紫球海胆基因组中被识别出来，并且很可能就是大约5.2亿年前最早的棘皮动物中参与立体骨针形成的相同基因。
