Dan Larhammar

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Johannes Zachhuber

University of Oxford

J. H. Chajes

University of Haifa

Remo Caponi

University of Cologne

Giulia Sissa

Ucla

Martin O'Neill

University of York

Enrico Cirelli

Università di Bologna

Bernd-Christian Otto

Friedrich-Alexander-Universität Erlangen-Nürnberg

Francesco Camia

Università degli Studi "La Sapienza" di Roma

Kati (Katalin) Prajda

University of Vienna

Seth Bernard

University of Toronto

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Papers by Dan Larhammar

Evolution of the Neuropeptide Y Family of Peptides

Humana Press eBooks, Nov 14, 2003

Identification of a new Kir6 potassium channel and comparison of properties of Kir6 subtypes by structural modelling and molecular dynamics

International Journal of Biological Macromolecules, Jul 1, 2023

In silico searches for putative growth hormone family homologs in invertebrates

Growth hormone, prolactin and somatolactin-family sequences were sought in diverse inver... more Growth hormone, prolactin and somatolactin-family sequences were sought in diverse invertebrate genome and reference sequence databases using different available strategies. None of these search strategies could identify any putative invertebrate GH/PRL/SL homologs with the characteristic amino acid motif of the family, or indeed any significant sequence similarity. One sequence with high sequence identity to human PRL was identified from a tapeworm species; however this sequence is likely the result of horizontal gene transfer or contamination. File information: In silico searches for putative growth hormone family homologs in invertebrates.pdf Description of methods and results, with references. 130723_Taenia_prl-hit_NJtree.phb Neighbor joining tree file in Newick format including the identified tapeworm sequence. Vertebrate species names are abbreviated to the first letter of the genus followed by the first two letters of the species (Hsa = Homo sapiens et. c.). The tapeworm sequence is identified with the UniProt ID Q8T110_9CEST. 130723_Taenia_prl-hit_NJtree.pdf Image of the neighbor joining tree (PDF). The tapeworm sequence is colored green. Pairwise_align_hPRL+Taenia_prl-hit.txt Text file with the results of the pairwise alignment between the human PRL sequence and the identified tapeworm sequence. HsaPRL+Taenia_prl-hit.aln Clustal alignment file containing the human PRL sequence and the identified tapeworm sequence. </p

Paralogous SSTR-gene bearing chromosome regions in the stickleback and zebrafish genomes

Published in: Ocampo Daza D, Sundström G, Bergqvist CA, Larhammar D. The evolution of vertebrate ... more Published in: Ocampo Daza D, Sundström G, Bergqvist CA, Larhammar D. The evolution of vertebrate somatostatin receptors and their gene regions involves extensive chromosomal rearrangements. BMC Evolutionary Biology 2012, 12:231 doi:10.1186/1471-2148-12-231. Please refer to this article if using this figure. Figure 7 Continued from Figure 6. Paralogous chromosome regions in the stickleback and zebrafish genomes. More rearrangements could be identified in the zebrafish genome than in the stickleback or medaka genomes.

Phylogenetic analyses of 47 syntenic gene families in SSTR gene-bearing chromosome regions

Sequence based phylogenetic analyses of 47 gene families identified in an analysis of conserved s... more

Cloning and pharmacological characterization of the neuropeptide Y receptor Y5 in the sea lamprey, Petromyzon marinus

Peptides, 2013

The neuropeptide Y system is known to have expanded in early vertebrate evolution. Three neuropep... more The neuropeptide Y system is known to have expanded in early vertebrate evolution. Three neuropeptide Y receptors have been proposed to have existed before the two basal vertebrate tetraploidizations, namely a Y1-like, a Y2-like, and a Y5-like receptor, with their genes in the same chromosomal region. Previously we have described a Y1-subfamily and a Y2-subfamily receptor in the river lamprey, Lampetra fluviatilis. Here we report the identification of a Y5 receptor in the genome of the sea lamprey, Petromyzon marinus. In phylogenetic analyses, the Y5 receptor clusters together with gnathostome Y5 receptors with high bootstrap value and shares the long intracellular loop 3. This lamprey receptor has an even longer loop 3 than the gnathostome Y5 receptors described so far, with the expansion of amino acid repeats. Functional expression in a human cell line, co-transfected with a modified human G-protein, resulted in inositol phosphate turnover in response to the three lamprey NPY-family peptides NPY, PYY and PMY at nanomolar concentrations. Our results confirm that the Y1-Y2-Y5 receptor gene triplet arose before the cyclostome-gnathostome divergence. However, it is not clear from the NPY receptors whether cyclostomes diverged from the gnathostome lineage after the first or the second tetraploidization. Duplicates resulting from the tetraploidizations exist for both Y1 and Y2 in gnathostomes, but only a single copy of Y5 has survived in all vertebrates characterized to date, making the physiological roles of Y5 interesting to explore.

Corticotropin-Releasing Hormone (CRH) Gene Family Duplications in Lampreys Correlate With Two Early Vertebrate Genome Doublings

Frontiers in Neuroscience, Jul 30, 2020

The ancestor of gnathostomes (jawed vertebrates) is generally considered to have undergone two ro... more The ancestor of gnathostomes (jawed vertebrates) is generally considered to have undergone two rounds of whole genome duplication (WGD). The timing of these WGD events relative to the divergence of the closest relatives of the gnathostomes, the cyclostomes, has remained contentious. Lampreys and hagfishes are extant cyclostomes whose gene families can shed light on the relationship between the WGDs and the cyclostome-gnathostome divergence. Previously, we have characterized in detail the evolution of the gnathostome corticotropin-releasing hormone (CRH) family and found that its five members arose from two ancestral genes that existed before the WGDs. The two WGDs resulted, after secondary losses, in one triplet consisting of CRH1, CRH2, and UCN1, and one pair consisting of UCN2 and UCN3. All five genes exist in representatives for cartilaginous fishes, ray-finned fishes, and lobe-finned fishes. Differential losses have occurred in some lineages. We present here analyses of CRH-family members in lamprey and hagfish by comparing sequences and gene synteny with gnathostomes. We found five CRH-family genes in each of two lamprey species (Petromyzon marinus and Lethenteron camtschaticum) and two genes in a hagfish (Eptatretus burgeri). Synteny analyses show that all five lamprey CRH-family genes have similar chromosomal neighbors as the gnathostome genes. The most parsimonious explanation is that the lamprey CRH-family genes are orthologs of the five gnathostome genes and thus arose in the same chromosome duplications. This suggests that lampreys and gnathostomes share the same two WGD events and that these took place before the lamprey-gnathostome divergence.

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