Discovery of Hyperactive Antifreeze Protein from Phylogenetically Distant Beetles Questions Its Evolutionary Origin
Beetle hyperactive antifreeze protein (AFP) has a unique ability to maintain a supercooling state of its body fluids, however, less is known about its origination. Here, we found that a popular stag beetle <i>Dorcus hopei binodulosus</i> (<i>Dhb</i>) synthesizes at least 6 is...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-03-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/22/7/3637 |
| Summary: | Beetle hyperactive antifreeze protein (AFP) has a unique ability to maintain a supercooling state of its body fluids, however, less is known about its origination. Here, we found that a popular stag beetle <i>Dorcus hopei binodulosus</i> (<i>Dhb</i>) synthesizes at least 6 isoforms of hyperactive AFP (<i>Dhb</i>AFP). Cold-acclimated <i>Dhb</i> larvae tolerated −5 °C chilled storage for 24 h and fully recovered after warming, suggesting that <i>Dhb</i>AFP facilitates overwintering of this beetle. A <i>Dhb</i>AFP isoform (~10 kDa) appeared to consist of 6−8 tandem repeats of a 12-residue consensus sequence (TCTxSxNCxxAx), which exhibited 3 °C of high freezing point depression and the ability of binding to an entire surface of a single ice crystal. Significantly, these properties as well as DNA sequences including the untranslated region, signal peptide region, and an AFP-encoding region of <i>Dhb</i> are highly similar to those identified for a known hyperactive AFP (<i>Tm</i>AFP) from the beetle <i>Tenebrio molitor</i> (<i>Tm</i>). Progenitor of <i>Dhb</i> and <i>Tm</i> was branched off approximately 300 million years ago, so no known evolution mechanism hardly explains the retainment of the DNA sequence for such a long divergence period. Existence of unrevealed gene transfer mechanism will be hypothesized between these two phylogenetically distant beetles to acquire this type of hyperactive AFP. |
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| ISSN: | 1661-6596 1422-0067 |