RT Journal Article
SR Electronic
T1 Genes lost during the transition from land to water in cetaceans highlight genomic changes associated with aquatic adaptations
JF Science Advances
JO Sci Adv
FD American Association for the Advancement of Science
SP eaaw6671
DO 10.1126/sciadv.aaw6671
VO 5
IS 9
A1 Huelsmann, Matthias
A1 Hecker, Nikolai
A1 Springer, Mark S.
A1 Gatesy, John
A1 Sharma, Virag
A1 Hiller, Michael
YR 2019
UL http://advances.sciencemag.org/content/5/9/eaaw6671.abstract
AB The transition from land to water in whales and dolphins (cetaceans) was accompanied by remarkable adaptations. To reveal genomic changes that occurred during this transition, we screened for protein-coding genes that were inactivated in the ancestral cetacean lineage. We found 85 gene losses. Some of these were likely beneficial for cetaceans, for example, by reducing the risk of thrombus formation during diving (F12 and KLKB1), erroneous DNA damage repair (POLM), and oxidative stress–induced lung inflammation (MAP3K19). Additional gene losses may reflect other diving-related adaptations, such as enhanced vasoconstriction during the diving response (mediated by SLC6A18) and altered pulmonary surfactant composition (SEC14L3), while loss of SLC4A9 relates to a reduced need for saliva. Last, loss of melatonin synthesis and receptor genes (AANAT, ASMT, and MTNR1A/B) may have been a precondition for adopting unihemispheric sleep. Our findings suggest that some genes lost in ancestral cetaceans were likely involved in adapting to a fully aquatic lifestyle.