High FST expression agrees with its expression in all vertebrates and with the finding that it is required for liver cell growth homeostasis in mice. This non-gonadal function of the gene may be conserved in coelacanths. Similarly the transcription factor GATA-4, besides a role in gene regulation in testis development, is also involved in the control of a Tulathromycin B number of liver genes, explaining why 3,4,5-Trimethoxyphenylacetic acid transcripts of the coelacanth homologue were found in both tissues. In contrast to coelacanths, where 5a-reductase 2 is highly expressed in liver, the 5a-reductase 1 isoform is differentially regulated by androgens and glucocorticoids in rat liver, resulting in high expression in this tissue, while 5a-reductase 2 is preferentially expressed in gonads. This may indicate lineage-specific subfunctionalization of the isozymes during evolution. The absence of SOX8 expression in Latimeria testis was unexpected. In other vertebrates, including teleost fish, it is readily detected in this organ, and in mammals it has been assigned an important function in the FGF9/SOX9 interaction loop to maintain Sertoli cell identity by acting redundantly to SOX9. Such back-up function does not seem to be required in Latimeria testis maintenance, or may have been lost in the extant coelacanth lineage. In medaka SOX9 is required for germ cell proliferation and survival, but not for testis determination. Together with the other L. menadoensis 
findings this may indicate that the sex-determining function was acquired later in tetrapod lineage, after the split of teleost and coelacanth lineages. Intriguing data were found for FGF9 and 20, which together with FGF16 constitute a gene subfamily of paracrine FGFs. The critical role of FGF9 in mammalian testis development is well established and appears to be conserved in all tetrapods. On the other hand, the gene is not found in any teleost genome, unlike FGF16 and 20. In the amphioxus an FGF gene is basal to the three FGFs in tetrapods. FGF9 could thus be a later duplicate of either FGF16 or 20, and its role in testis development could be interpreted as an innovation arising in tetrapods. However, identification of FGF9 in Latimeria supports an origin during the 1R/2R whole genome duplication events that took place in ancestral chordates and its loss in the lineage leading to teleosts. In the teleost Oreochromis niloticus FGF20b and FGF16 are both expressed in ovary, whereas only FGF16 is expressed in testis. Together with the complete absence of FGF9, FGF20 and FGF16 expression in L. menadoensis liver and testis, this indicates that the function of FGF signalling in testis, in particular the central role of FGF9, was acquired later in tetrapod evolution. Surprisingly, the ERb gene was expressed in the liver of the male coelacanth. A previous study of the same individual had disclosed expression of the vitellogenin genes vtgABI, II and III. Vitellogenins are yolk proteins physiologically expressed in the liver of reproductive females upon induction by oestrogens. Thus expression of vitellogenins and oestrogen receptor indicates the presence of oestrogens in this male specimen. They could derive from environment pollutants, as reported in a number of specimens from polluted waters; however this individual lived in Bunaken Marine Park in submarine caves at a depth of 100 to 200 m, i.e. in a relatively protected environment.