When the brain goes diving: transcriptome analysis reveals a reduced aerobic energy metabolism and increased stress proteins in the seal brain

Table 1 Most highly expressed genes in the visual cortex of the hooded seal (A) and ferret (B)

Gene	Gene symbol	Function	Hooded seal (RPKM)	Ferret (RPKM)	Fold difference
A. Hooded seal
Clusterin	CLU	Chaperone	3104.57	777.62	3.99
Prostaglandin D2 synthase	PTGDS	Neuromodulator	2213.95	1451.49	1.53
S100 calcium binding protein B	S100B	Ca²⁺-binding regulator	1860.29	48.98	37.98
Glyceraldehyde-3-phosphate dehydrogenase	GAPDH	Metabolic enzyme	1413.17	3728.00	−2.64
Glycerophosphodiester phosphodiesterase domain containing 2	GDPD2	Lipid metabolism	1334.93	277.95	4.80
Glutamate-ammonia ligase	GLUL	pH control, removal of ammonia and L-glutamate	1046.64	768.49	1.36
Calmodulin 2	CALM2	Ca²⁺-binding regulator	1002.24	1805.51	−1.80
SPARC-like 1 (hevin)	SPARCL1	Ca²⁺-binding	938.95	536.88	1.75
Aldolase C, fructose-bisphosphate	ALDOC	Metabolic enzyme	918.67	906.26	1.01
Prosaposin	PSAP	Lipid metabolism	883.57	913.66	−1.03
B. Ferret
Glyceraldehyde-3-phosphate dehydrogenase	GAPDH	Metabolic enzyme	1413.17	3728.00	−2.64
Mitochondrially Encoded Cytochrome C Oxidase II	MTCO2	Respiratory chain	245.64	2266.01	−9.22
Peptidyl-prolyl cis-trans isomerase E-like	LOC101679695	Unknown	98.39	1824.67	−18.55
Calmodulin 2	CALM2	Ca²⁺-binding regulator	1002.24	1805.51	−1.80
Calmodulin 1	CALM1	Ca²⁺-binding regulator	480.64	1802.73	−3.75
Prostaglandin D2 synthase	PTGDS	Neuromodulator	2213.95	1451.49	1.53
Mitochondrial ATP synthase, Beta subunit	ATP5B	Respiratory chain	541.42	1166.96	−2.16
Lactate dehydrogenase B	LDHB	Metabolic enzyme	453.40	1127.78	−2.49
Malate Dehydrogenase 1, NAD	MDH1	Metabolic enzyme	544.42	1055.62	−1.94
Ribosomal protein L26	RPL26	Translation	289.61	1040.08	−3.59

ISSN: 1471-2164