Central to the pathways that induce cell growth in mammals is the murine target of rapamycin (mTOR), a multi-domain, 298 kDa, evolutionarily-conserved Ser/Thr kinase that is inhibited by the drug rapamycin (Schmelzle and Hall, 2000). mTOR exerts its effects by phosphorylating eukaryotic initiation factor 4E binding protein 1 (4EBP1), which inhibits 5′-cap-dependent mRNA translation (the majorit...

DNA damage causes chromosomal instability leading to oncogenesis, apoptosis, and severe failure of cell functions. The DNA repair system includes base excision repair, nucleotide excision repair, mismatch repair, translesion replication, non-homologous end-joining, and recombinational repair. Homologous recombination performs the recombinational repair. The gene is an ortholog of , and the gene...

DNA barcoding provides an operational framework for mammalian taxonomic identification and cryptic species discovery. Focused effort to build a reference library of genetic data has resulted in the assembly of over 35 K mammalian cytochrome c oxidase subunit I sequences and outlined the scope of mammal-related barcoding projects. Based on the above experience, this chapter recounts three typica...

Osmoregulation in marine mammals has been investigated for over a century; however, a review of recent advances in our understanding of water and electrolyte balance and of renal function in marine mammals is warranted. The following topics are discussed: (i) kidney structure and urine concentrating ability, (ii) sources of water, (iii) the effects of feeding, fasting and diving, (iv) the renal...

Communication is a process by which a sender produces a signal, which alters the probability of a subsequent behav­ ior in a receiver(s). Often, but not always, communication facilitates social behavior. Given the highly social behavior found in many marine mammals, the study of communicative behavior is essential to understanding the role that signaling plays in regulating social interactions ...

A handful of autosomal genes in the mammalian genome are inherited in a silent state from one of the two parents, and in a fully active form from the other, thereby rendering the organism functionally hemizygous for imprinted genes. To date 19 imprinted genes have been identified; 5 are expressed from the maternal chromosome while the rest are expressed from the paternal chromosome. Allele-spec...

Brucella infections have recently been recognized in seals, sea lions, walruses, dolphins, porpoises, whales and an otter. This organism appears to be widespread in marine mammals, and has probably been endemic in these populations for a long time. The clinical significance is uncertain. A few infections have been associated with placentitis/abortions, neonatal mortality, meningoencephalitis, a...

Understanding an animal’s nutritional niche is fundamental to a full appreciation of its ecology , and is important for both pest control and species conservation purposes. Carnivores have digestive systems dominated by the small intestine , which can be related to the generally high digestibility of their food. Omnivores have more complex gastrointestinal tracts , with a hindgut caecum in whic...