Circadian genes in a blind subterranean mammal II: Conservation and uniqueness of the three<i>Period</i>homologs in the blind subterranean mole rat,<i>Spalax ehrenbergi</i>superspecies

Avivi, Aaron; Oster, Henrik; Joel, Alma; Beiles, Avigdor; Albrecht, Urs; Nevo, Eviatar

doi:10.1073/pnas.182423299

Cited by 41 publications

(36 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The circadian rhythm of the BMR has been previously studied and genes involved were identified [58][59][60] . Multi-alignments of the protein sequences of circadian genes revealed that both BMR and NMR CLOCK proteins have an expanded Q-rich region compared with that of the human and mouse, and are different in amino-acid composition from that of the rat 58 (Fig.…”

Section: Resultsmentioning

confidence: 99%

Genome-wide adaptive complexes to underground stresses in blind mole rats Spalax

Fang¹,

Nevo²,

Han³

et al. 2014

Nat Commun

Self Cite

134

139

View full text Add to dashboard Cite

The blind mole rat (BMR), Spalax galili, is an excellent model for studying mammalian adaptation to life underground and medical applications. The BMR spends its entire life underground, protecting itself from predators and climatic fluctuations while challenging it with multiple stressors such as darkness, hypoxia, hypercapnia, energetics and high pathonecity. Here we sequence and analyse the BMR genome and transcriptome, highlighting the possible genomic adaptive responses to the underground stressors. Our results show high rates of RNA/DNA editing, reduced chromosome rearrangements, an over-representation of short interspersed elements (SINEs) probably linked to hypoxia tolerance, degeneration of vision and progression of photoperiodic perception, tolerance to hypercapnia and hypoxia and resistance to cancer. The remarkable traits of the BMR, together with its genomic and transcriptomic information, enhance our understanding of adaptation to extreme environments and will enable the utilization of BMR models for biomedical research in the fight against cancer, stroke and cardiovascular diseases.

show abstract

Section: Resultsmentioning

confidence: 99%

Genome-wide adaptive complexes to underground stresses in blind mole rats Spalax

Fang¹,

Nevo²,

Han³

et al. 2014

Nat Commun

Self Cite

134

139

View full text Add to dashboard Cite

show abstract

“…For example, in insects that have both Tim1 and the Cry-d, such as the fly Sarcophaga crassipalpis (Goto and Denlinger 2002) and the moths Bombyx mori (Iwai et al 2006) and Antheraea pernyi (Sauman and Reppert 1996), Tim1 and Per mRNA oscillate with a similar phase. The situation is more complex in vertebrates that have multiple paralogs for CRY and PER, but still there is evidence that Cry products oscillate with strong amplitude and a phase similar to that of Per in the mouse and other vertebrates that have only the mouse type Cry and Tim2 (see Yoshimura et al 2000;Avivi et al 2002Avivi et al , 2004Fu et al 2002). The temporal pattern of gene expression in the honey bee brain is strikingly distinct from Drosophila.…”

Section: Discussionmentioning

confidence: 99%

Molecular and phylogenetic analyses reveal mammalian-like clockwork in the honey bee (Apis mellifera) and shed new light on the molecular evolution of the circadian clock

et al. 2006

View full text Add to dashboard Cite

The circadian clock of the honey bee is implicated in ecologically relevant complex behaviors. These include time sensing, time-compensated sun-compass navigation, and social behaviors such as coordination of activity, dance language communication, and division of labor. The molecular underpinnings of the bee circadian clock are largely unknown. We show that clock gene structure and expression pattern in the honey bee are more similar to the mouse than to Drosophila. The honey bee genome does not encode an ortholog of Drosophila Timeless (Tim1), has only the mammalian type Cryptochrome (Cry-m), and has a single ortholog for each of the other canonical "clock genes." In foragers that typically have strong circadian rhythms, brain mRNA levels of amCry, but not amTim as in Drosophila, consistently oscillate with strong amplitude and a phase similar to amPeriod (amPer) under both light-dark and constant darkness illumination regimes. In contrast to Drosophila, the honey bee amCYC protein contains a transactivation domain and its brain transcript levels oscillate at virtually an anti-phase to amPer, as it does in the mouse. Phylogenetic analyses indicate that the basal insect lineage had both the mammalian and Drosophila types of Cry and Tim. Our results suggest that during evolution, Drosophila diverged from the ancestral insect clock and specialized in using a set of clock gene orthologs that was lost by both mammals and bees, which in turn converged and specialized in the other set. These findings illustrate a previously unappreciated diversity of insect clockwork and raise critical questions concerning the evolution and functional significance of species-specific variation in molecular clockwork.

show abstract

“…Of special interest is the high expression of heparanase in the Spalax eye (Fig. 4B, lane 6), which is atrophic and visually blind (16,17), but is assessing photoperiodicity by responding to signals that penetrate the soil and is also involved in the circadian rhythm control (40)(41)(42).…”

Section: Discussionmentioning

confidence: 99%

Adaptive evolution of heparanase in hypoxia-tolerantSpalax: Gene cloning and identification of a unique splice variant

Nasser

Nevo

Shafat

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

Heparan sulfate (HS) side chains of HS proteoglycans bind to and assemble extracellular matrix proteins and play important roles in cell-cell and cell-extracellular matrix interactions. HS chains bind a multitude of bioactive molecules and thereby function in the control of multiple normal and pathological processes. Enzymatic degradation of HS by heparanase, a mammalian endoglycosidase, affects the integrity and functional state of tissues and is involved in, among other processes, inflammation, angiogenesis, and cancer metastasis. Here, we report the cloning of heparanase from four Israeli species of the blind subterranean mole rat (Spalax ehrenbergi superspecies), 85% homologous to the human enzyme. Unlike its limited expression in human tissues, heparanase is highly expressed in diverse Spalax tissues. Moreover, we have identified a unique splice variant of the Spalax enzyme lacking 16 aa encoded by exon 7. This deletion resulted in a major defect in trafficking and processing of the heparanase protein, leading to a loss of its enzymatic activity. Interspecies variation was noted in the sequence and in the expression of the splice variant of the heparanase gene in blind mole rats living under different ecogeographical stresses, indicating a possible role in adaptation to stress in Spalax evolution.alternative splicing ͉ heparan sulfate ͉ blind mole rat ͉ angiogenesis ͉ cancer H eparan sulfate (HS) proteoglycans are macromolecules associated with the cell surface and the extracellular matrix (ECM) of a wide range of cells of vertebrate and invertebrate tissues (1-3). HS binds to and assembles ECM proteins and plays important roles in the structural integrity of the ECM and in cell-cell and cell-ECM interactions. HS chains sequester a multitude of proteins and bioactive molecules and thereby function in the control of a large number of normal and pathological processes (1-4). Apart from sequestration of bioactive molecules, HS proteoglycans have a coreceptor role in which the proteoglycan, in concert with the other cell surface molecule, comprises a functional receptor complex that binds the ligand and mediates its action (3-5).Enzymatic degradation of HS by heparanase, a mammalian endoglucuronidase, affects the integrity and functional state of tissues and is involved in fundamental biological phenomena, ranging from pregnancy, morphogenesis, and development to inf lammation, angiogenesis, and cancer metastasis (6 -10). Heparanase elicits an indirect angiogenic response by releasing HS-bound angiogenic growth factors [e.g., basic fibroblast growth factor and vascular endothelial growth factor (VEGF)] from the ECM and by generating HS fragments that potentiate basic fibroblast growth factor receptor binding, dimerization, and signaling (5, 8). Despite earlier reports on the existence of several distinct mammalian HS-degrading endoglycosidases (heparanases), the cloning of the same single gene by several groups (6,7,11,12) suggests that mammalian cells express primarily a single dominant functional heparanase e...

show abstract

Circadian genes in a blind subterranean mammal II: Conservation and uniqueness of the threePeriodhomologs in the blind subterranean mole rat,Spalax ehrenbergisuperspecies

Cited by 41 publications

References 50 publications

Genome-wide adaptive complexes to underground stresses in blind mole rats Spalax

Genome-wide adaptive complexes to underground stresses in blind mole rats Spalax

Molecular and phylogenetic analyses reveal mammalian-like clockwork in the honey bee (Apis mellifera) and shed new light on the molecular evolution of the circadian clock

Adaptive evolution of heparanase in hypoxia-tolerantSpalax: Gene cloning and identification of a unique splice variant

Contact Info

Product

Resources

About