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Paul H Weigel - One of the best experts on this subject based on the ideXlab platform.
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the cytoplasmic domain of the hyaluronan receptor for endocytosis Hare contains multiple endocytic motifs targeting coated pit mediated internalization
Journal of Biological Chemistry, 2008Co-Authors: Madhu S Pandey, Janet A Weigel, Edward N Harris, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare) is the primary scavenger receptor for HA and chondroitin sulfates in mammals. The two human isoforms of Hare (full-length 315-kDa and a 190-kDa proteolytic cleavage product), which are type I single-pass membrane proteins, are highly expressed in sinusoidal endothelial cells of lymph nodes, liver, and spleen. Their identical Hare cytoplasmic domains contain four candidate AP-2/clathrin-mediated endocytic signaling motifs as follows: YSYFRI2485, FQHF2495, NPLY2519, and DPF2534 (315-Hare numbering). Stably transfected cells expressing 190-Hare(ΔYSYFRI), 190-Hare(ΔFQHF), or 190-Hare(ΔNPLY) (lacking Motifs 1, 2, or 3) had decreased 125I-HA endocytosis rates of ∼49, ∼39, and ∼56%, respectively (relative to wild type). In contrast, 190-Hare(ΔDPF) cells (lacking Motif 4) showed no change in HA endocytic rate. Deletions of motifs 1 and 2 or of 1, 2, and 4 decreased the rate of HA endocytosis by only ∼41%. Endocytosis was ∼95% decreased in mutants lacking all four motifs. Cells expressing a 190-Hare(Y2519A) mutant of the NPLY motif retained 85–90% of wild type endocytosis, whereas this mutation in the triple motif deletant decreased endocytosis to ∼7% of wild type. Tyr in NPLY2519 is thus important for endocytosis. All Hare mutants showed similar HA binding and degradation of the internalized HA, indicating that altering endocytic motifs did not affect ectodomain binding of HA or targeting of internalized HA to lysosomes. We conclude that, although NPLY may be the most important motif, it functions together with two other endocytic motifs; thus three signal sequences (YSYFRI, FQHF, and NPLY) provide redundancy to mediate coated pit targeting and endocytosis of Hare.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
Edward N Harris - One of the best experts on this subject based on the ideXlab platform.
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the cytoplasmic domain of the hyaluronan receptor for endocytosis Hare contains multiple endocytic motifs targeting coated pit mediated internalization
Journal of Biological Chemistry, 2008Co-Authors: Madhu S Pandey, Janet A Weigel, Edward N Harris, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare) is the primary scavenger receptor for HA and chondroitin sulfates in mammals. The two human isoforms of Hare (full-length 315-kDa and a 190-kDa proteolytic cleavage product), which are type I single-pass membrane proteins, are highly expressed in sinusoidal endothelial cells of lymph nodes, liver, and spleen. Their identical Hare cytoplasmic domains contain four candidate AP-2/clathrin-mediated endocytic signaling motifs as follows: YSYFRI2485, FQHF2495, NPLY2519, and DPF2534 (315-Hare numbering). Stably transfected cells expressing 190-Hare(ΔYSYFRI), 190-Hare(ΔFQHF), or 190-Hare(ΔNPLY) (lacking Motifs 1, 2, or 3) had decreased 125I-HA endocytosis rates of ∼49, ∼39, and ∼56%, respectively (relative to wild type). In contrast, 190-Hare(ΔDPF) cells (lacking Motif 4) showed no change in HA endocytic rate. Deletions of motifs 1 and 2 or of 1, 2, and 4 decreased the rate of HA endocytosis by only ∼41%. Endocytosis was ∼95% decreased in mutants lacking all four motifs. Cells expressing a 190-Hare(Y2519A) mutant of the NPLY motif retained 85–90% of wild type endocytosis, whereas this mutation in the triple motif deletant decreased endocytosis to ∼7% of wild type. Tyr in NPLY2519 is thus important for endocytosis. All Hare mutants showed similar HA binding and degradation of the internalized HA, indicating that altering endocytic motifs did not affect ectodomain binding of HA or targeting of internalized HA to lysosomes. We conclude that, although NPLY may be the most important motif, it functions together with two other endocytic motifs; thus three signal sequences (YSYFRI, FQHF, and NPLY) provide redundancy to mediate coated pit targeting and endocytosis of Hare.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
Janet A Weigel - One of the best experts on this subject based on the ideXlab platform.
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the cytoplasmic domain of the hyaluronan receptor for endocytosis Hare contains multiple endocytic motifs targeting coated pit mediated internalization
Journal of Biological Chemistry, 2008Co-Authors: Madhu S Pandey, Janet A Weigel, Edward N Harris, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare) is the primary scavenger receptor for HA and chondroitin sulfates in mammals. The two human isoforms of Hare (full-length 315-kDa and a 190-kDa proteolytic cleavage product), which are type I single-pass membrane proteins, are highly expressed in sinusoidal endothelial cells of lymph nodes, liver, and spleen. Their identical Hare cytoplasmic domains contain four candidate AP-2/clathrin-mediated endocytic signaling motifs as follows: YSYFRI2485, FQHF2495, NPLY2519, and DPF2534 (315-Hare numbering). Stably transfected cells expressing 190-Hare(ΔYSYFRI), 190-Hare(ΔFQHF), or 190-Hare(ΔNPLY) (lacking Motifs 1, 2, or 3) had decreased 125I-HA endocytosis rates of ∼49, ∼39, and ∼56%, respectively (relative to wild type). In contrast, 190-Hare(ΔDPF) cells (lacking Motif 4) showed no change in HA endocytic rate. Deletions of motifs 1 and 2 or of 1, 2, and 4 decreased the rate of HA endocytosis by only ∼41%. Endocytosis was ∼95% decreased in mutants lacking all four motifs. Cells expressing a 190-Hare(Y2519A) mutant of the NPLY motif retained 85–90% of wild type endocytosis, whereas this mutation in the triple motif deletant decreased endocytosis to ∼7% of wild type. Tyr in NPLY2519 is thus important for endocytosis. All Hare mutants showed similar HA binding and degradation of the internalized HA, indicating that altering endocytic motifs did not affect ectodomain binding of HA or targeting of internalized HA to lysosomes. We conclude that, although NPLY may be the most important motif, it functions together with two other endocytic motifs; thus three signal sequences (YSYFRI, FQHF, and NPLY) provide redundancy to mediate coated pit targeting and endocytosis of Hare.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
Svetlana V Kyosseva - One of the best experts on this subject based on the ideXlab platform.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
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expression processing and glycosaminoglycan binding activity of the recombinant human 315 kda hyaluronic acid receptor for endocytosis Hare
Journal of Biological Chemistry, 2007Co-Authors: Edward N Harris, Janet A Weigel, Svetlana V Kyosseva, Paul H WeigelAbstract:Abstract The hyaluronic acid (HA) receptor for endocytosis (Hare; also designated stabilin-2 and FEEL-2) mediates systemic clearance of glycosaminoglycans from the circulatory and lymphatic systems via coated pit-mediated uptake. Hare is primarily found as two isoforms (315- and 190-kDa) in sinusoidal endothelial cells of the liver, lymph node, and spleen. Here we characterize the ligand specificity and function of the large stably expressed 315-Hare isoform in Flp-In 293 cell lines. Like human spleen sinusoidal endothelial cells, Flp-In 293 cell lines transfected with a single cDNA encoding the full-length 315-Hare express both the 315-kDa and the proteolytically truncated 190-kDa isoforms in a ratio of ∼3–4:1. The 190-kDa Hare isoform generated from the 315-kDa Hare and the 315-kDa Hare specifically bound 125I-HA. Like the 190-kDa Hare expressed alone (Harris, E. N., Weigel, J. A., and Weigel, P. H. (2004) J. Biol. Chem. 279, 36201–36209), the 190- and 315-kDa Hare isoforms expressed in 315-Hare cell lines were recognized by anti-Hare monoclonal antibodies 30, 154, and 159. All 315-Hare cell lines could endocytose and degrade 125I-HA. Competition studies with live cells indicate that 190-Hare and 315-Hare bind HA with higher apparent affinity (Kd ∼10–20 nm) than chondroitin sulfate (CS) types A, C, D, or E. Only slight competition of HA endocytosis was observed with CS-B (dermatan sulfate) and chondroitin. Direct binding assays with the 315-Hare ectodomain revealed high affinity HA binding, and lower binding affinities for CS-C, CS-D, and CS-E. A majority of each Hare isoform was intracellular, within the endocytic system, suggesting transient surface residency typical of an active endocytic recycling receptor.
Neil Reid - One of the best experts on this subject based on the ideXlab platform.
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Mountain Hare transcriptome and diagnostic markers as resources to monitor hybridization with European Hares.
Scientific Data, 2017Co-Authors: João P. Marques, Mafalda S. Ferreira, Liliana Farelo, Colin M. Callahan, Klaus Hackländer, Hannes Jenny, W. Ian Montgomery, Neil Reid, Jeffrey M. Good, Paulo C. AlvesAbstract:We report the first mountain Hare (Lepus timidus) transcriptome, produced by de novo assembly of RNA-sequencing reads. Data were obtained from eight specimens sampled in two localities, Alps and Ireland. The mountain Hare tends to be replaced by the invading European Hare (Lepus europaeus) in their numerous contact zones where the species hybridize, which affects their gene pool to a yet unquantified degree. We characterize and annotate the mountain Hare transcriptome, detect polymorphism in the two analysed populations and use previously published data on the European Hare (three specimens, representing the European lineage of the species) to identify 4 672 putative diagnostic sites between the species. A subset of 85 random independent SNPs was successfully validated using PCR and Sanger sequencing. These valuable genomic resources can be used to design tools to assess population status and monitor hybridization between species.
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Niche overlap of mountain Hare subspecies and the vulnerability of their ranges to invasion by the European Hare; the (bad) luck of the Irish
Biological Invasions, 2016Co-Authors: Anthony Caravaggi, W. Ian Montgomery, Pekka Helle, Francesco Bisi, Adriano Martinoli, Katie Leach, F. Santilli, Jukka Rintala, Juha Tiainen, Neil ReidAbstract:Niche conservatism is the tendency of related species to retain ancestral tolerances after geographic separation. We used Ecological Niche Modelling and Principal Components Analysis of bioclimatic and habitat variables to describe the extent of the species niche, and degrees of bioclimatic–habitat niche conservatism within the mountain Hare (L. timidus) clade. Mountain Hare niche space was contrasted with that of the European Hare (L. europaeus), to shed light on species interactions in contact zones throughout Europe. All five subspecies of mountain Hare had quantifiably distinct niches. Fennoscandian (L.t. sylvaticus, L.t. timidus) and highland (L.t. scoticus, L.t. varronis) subspecies, however, were most similar, exhibiting greatest apparent niche conservatism. They inhabit tundra, boreal forest and uplands, and, hence are presumed most similar to the ancestral form. The Irish Hare was distinct, being consistently distinguished from other mountain Hares in both 2D and nth dimensional (4D) niche space. The ecological distinctiveness of the Irish Hare provides further evidence that it is an Evolutionarily Significant Unit, particularly vulnerable to displacement by introduced European Hares with which it competes and hybridises. Projections under global climate change suggest that, by 2070, bioclimatic space for invasive European Hares in Ireland will expand (by 79%) but contract for endemic Irish Hares (by 75%), further facilitating their replacement. The near complete species replacement of the heath Hare (L.t. sylvaticus) in southern Sweden, where the European Hare has also been introduced, may suggest a similar fate may be in store for the Irish Hare.
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European Hare (Lepus europaeus) invasion ecology: implication for the conservation of the endemic Irish Hare (Lepus timidus hibernicus)
Biological Invasions, 2011Co-Authors: Neil ReidAbstract:European Hare Lepus europaeus populations have undergone recent declines but the species has successfully naturalised in many countries outside its native range. It was introduced to Ireland during the mid-late nineteenth century for field sport and is now well established in Northern Ireland. The native Irish Hare Lepus timidus hibernicus is an endemic subspecies of mountain Hare L. timidus and has attracted major conservation concern following a long-term population decline during the twentieth century and is one of the highest priority species for conservation action in Ireland. Little is known about the European Hare in Ireland or whether it poses a significant threat to the native mountain Hare subspecies by compromising its ecological security or genetic integrity. We review the invasion ecology of the European Hare and examine evidence for interspecific competition with the mountain Hare for habitat space and food resources, interspecific hybridisation, disease and parasite transmission and possible impacts of climate change. We also examine the impact that introduced Hares can have on native non-lagomorph species. We conclude that the European Hare is an emerging and significant threat to the conservation status of the native Irish Hare. Invasive mammal species have been successfully eradicated from Ireland before and immediate action is often the only opportunity for cost-effective eradication. An urgent call is issued for further research whilst the need for a European Hare invasive Species Action Plan (iSAP) and Eradication strategy are discussed.
