The genome of horseshoe crab Tachypleus tridentatus reveals its evolutionary scenario and well-developed innate immunity
Background
Horseshoe crabs are ancient marine arthropods with a long evolutionary history.
Results
Here, we describe the 2.06 Gbp genome assembly of Tachypleus tridentatus with predicted 24,222 protein-coding genes. Comparative genomics show that T. tridentatus and the Atlantic horseshoe crab Limulus polyphemus had the most orthologs shared in only these two species, including genes involved in immune related Jak/STAT signaling pathway. Divergence time dating results show that the last common ancestor of Asian horseshoe crabs (including T. tridentatus) and L. polyphemus appeared at about 130 Mya (121-141) and the split of two Asian horseshoe crabs was dated to about 63 Mya (57-69). Hox gene analysis suggests two clusters in both horseshoe crab assemblies. Surprisingly, selective analysis of immune related gene families revealed high expansion of conservatively presented pattern recognition receptors. Genes involved in IMD and Jak/STAT signaling transduction pathways also exhibited a certain degree of expansion in both genomes. Intact coagulation cascade related genes were presented in T. tridentatus genome with a higher number of coagulation factor genes. Moreover, most antibacterial peptides reported have been identified in T. tridentatus with their potentially effective antimicrobial sites.
Conclusions
The well-developed innate immunity of T.tridentatus may affect the quality of the adaptive properties with regard to complicated marine environments.
Figure 1
Figure 2
Figure 3
Figure 4
This is a list of supplementary files associated with this preprint. Click to download.
On 10 Feb, 2020
On 13 Jan, 2020
On 13 Jan, 2020
On 12 Jan, 2020
On 12 Jan, 2020
On 08 Jan, 2020
On 08 Jan, 2020
On 03 Jan, 2020
On 27 Dec, 2019
On 26 Dec, 2019
On 26 Dec, 2019
On 17 Dec, 2019
Received 05 Dec, 2019
Received 05 Dec, 2019
Invitations sent on 20 Nov, 2019
On 20 Nov, 2019
On 20 Nov, 2019
On 12 Nov, 2019
On 11 Nov, 2019
On 11 Nov, 2019
On 20 Oct, 2019
Received 17 Oct, 2019
Received 11 Sep, 2019
On 25 Aug, 2019
Invitations sent on 25 Aug, 2019
On 25 Aug, 2019
On 12 Aug, 2019
On 11 Aug, 2019
On 11 Aug, 2019
Posted 01 May, 2019
On 22 Jun, 2019
Received 16 Jun, 2019
Received 14 Jun, 2019
On 27 May, 2019
On 25 May, 2019
Invitations sent on 07 May, 2019
On 30 Apr, 2019
On 30 Apr, 2019
On 30 Apr, 2019
On 21 Apr, 2019
The genome of horseshoe crab Tachypleus tridentatus reveals its evolutionary scenario and well-developed innate immunity
On 10 Feb, 2020
On 13 Jan, 2020
On 13 Jan, 2020
On 12 Jan, 2020
On 12 Jan, 2020
On 08 Jan, 2020
On 08 Jan, 2020
On 03 Jan, 2020
On 27 Dec, 2019
On 26 Dec, 2019
On 26 Dec, 2019
On 17 Dec, 2019
Received 05 Dec, 2019
Received 05 Dec, 2019
Invitations sent on 20 Nov, 2019
On 20 Nov, 2019
On 20 Nov, 2019
On 12 Nov, 2019
On 11 Nov, 2019
On 11 Nov, 2019
On 20 Oct, 2019
Received 17 Oct, 2019
Received 11 Sep, 2019
On 25 Aug, 2019
Invitations sent on 25 Aug, 2019
On 25 Aug, 2019
On 12 Aug, 2019
On 11 Aug, 2019
On 11 Aug, 2019
Posted 01 May, 2019
On 22 Jun, 2019
Received 16 Jun, 2019
Received 14 Jun, 2019
On 27 May, 2019
On 25 May, 2019
Invitations sent on 07 May, 2019
On 30 Apr, 2019
On 30 Apr, 2019
On 30 Apr, 2019
On 21 Apr, 2019
Background
Horseshoe crabs are ancient marine arthropods with a long evolutionary history.
Results
Here, we describe the 2.06 Gbp genome assembly of Tachypleus tridentatus with predicted 24,222 protein-coding genes. Comparative genomics show that T. tridentatus and the Atlantic horseshoe crab Limulus polyphemus had the most orthologs shared in only these two species, including genes involved in immune related Jak/STAT signaling pathway. Divergence time dating results show that the last common ancestor of Asian horseshoe crabs (including T. tridentatus) and L. polyphemus appeared at about 130 Mya (121-141) and the split of two Asian horseshoe crabs was dated to about 63 Mya (57-69). Hox gene analysis suggests two clusters in both horseshoe crab assemblies. Surprisingly, selective analysis of immune related gene families revealed high expansion of conservatively presented pattern recognition receptors. Genes involved in IMD and Jak/STAT signaling transduction pathways also exhibited a certain degree of expansion in both genomes. Intact coagulation cascade related genes were presented in T. tridentatus genome with a higher number of coagulation factor genes. Moreover, most antibacterial peptides reported have been identified in T. tridentatus with their potentially effective antimicrobial sites.
Conclusions
The well-developed innate immunity of T.tridentatus may affect the quality of the adaptive properties with regard to complicated marine environments.
Figure 1
Figure 2
Figure 3
Figure 4