Abstract
The red sea urchin, Mesocentrotus franciscanus, is one the earth’s longest-lived animals, reported to live more than 100 years with indeterminate growth, life-long reproduction and no increase in mortality rate with age. To gain insight into mechanisms associated with longevity and negligible senescence, age-related transcriptional profiles were examined in tissues of the red sea urchin. Genome-wide transcriptional profiling using RNA-Seq revealed few age-related changes in gene expression in muscle and esophagus tissue. In contrast, radial nerve showed an unexpected level of complexity with the expression of 3,370 genes significantly altered more than two-fold with age, including genes involved in nerve function, signaling, metabolism, transcriptional regulation and chromatin modification. There was an age-related upregulation in expression of genes involved in synaptogenesis, axonogenesis and neuroprotection suggesting preservation of neuronal processes with age. There was also an upregulation in expression of positive regulators and key components of the AMPK pathway, autophagy, proteasome function, and the unfolded protein response. This unique age-related gene expression profile in the red sea urchin nervous system may play a role in mitigating the detrimental effects of aging in this long-lived animal.
Highlights
Gene expression is a key determinant of cellular phenotype, and genome-wide expression analysis can provide insight into the molecular events underlying complex processes such as aging
Collections of M. fransciscanus were conducted at the same geographic location and at the same time of year over three years in an attempt to mitigate selecting changes in gene expression that were due to seasonal variation or environmental factors particular to any one year
Ages of individual sea urchins were estimated from test diameter using growth curves generated from the weighted mean of the Tanaka parameters for M. franciscanus from tetracycline tagging experiments conducted near our collection site (f = 0.22929, d = 6.07531, a = 0.19906)[25,26] (Table 1)
Summary
Gene expression is a key determinant of cellular phenotype, and genome-wide expression analysis can provide insight into the molecular events underlying complex processes such as aging. Age-related gene expression profiles of the short-lived model animals Caenorhabditis elegans and Drosophila melanogaster share a common adult-onset expression program of genes involved in mitochondrial metabolism, DNA repair, catabolism, peptidolysis and cellular transport[3]. Gene expression profiles from mice, rats, and humans revealed a common signature of aging in mammals involving overexpression of inflammation and immune response genes and reduced expression of genes associated with mitochondrial function[1,4,5]. The purple sea urchin, Strongylocentrotus purpuratus, is reported to live for more than 50 years[21,22] and, like long-lived rodents, its tissues (muscle, esophagus and nerve) show few age-related changes in gene expression[23]. Based on data from long-lived animals such as the purple sea urchin it has been proposed that lifelong transcriptional stability may be a key determinant of exceptional longevity and negligible senescence[24]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
