Expression of Abdominal-B in the brine shrimp, Artemia franciscana, expands our evolutionary understanding of the crustacean abdomen

Jennifer B McCarthy-Taylor; Sophia R Kelly; Annalisa M VanHook; Henrique Marques-Souza; Julia M Serano; Nipam H Patel

doi:10.1016/j.ydbio.2022.06.011

Expression of Abdominal-B in the brine shrimp, Artemia franciscana, expands our evolutionary understanding of the crustacean abdomen

Dev Biol. 2022 Sep:489:178-184. doi: 10.1016/j.ydbio.2022.06.011. Epub 2022 Jun 19.

Authors

Jennifer B McCarthy-Taylor¹, Sophia R Kelly², Annalisa M VanHook³, Henrique Marques-Souza⁴, Julia M Serano⁵, Nipam H Patel⁶

Affiliations

¹ Department of Integrative Biology, University of California, Berkeley, CA, USA; Marine Biological Laboratory, Woods Hole, MA, USA.
² Marine Biological Laboratory, Woods Hole, MA, USA.
³ Department of Integrative Biology, University of California, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA; Science Signaling, AAAS, Washington, DC, USA.
⁴ Department of Integrative Biology, University of California, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA; Institute of Biology, University of Campinas, Campinas, Brazil.
⁵ Department of Integrative Biology, University of California, Berkeley, CA, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA; Independent Scholar, PO Box 11133, Oakland, CA, 94611-1133, USA.
⁶ Department of Integrative Biology, University of California, Berkeley, CA, USA; Marine Biological Laboratory, Woods Hole, MA, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA; Department of Organismal Biology and Anatomy and Molecular Genetics and Cell Biology, University of Chicago, IL, USA. Electronic address: npatel@mbl.edu.

PMID: 35732224
DOI: 10.1016/j.ydbio.2022.06.011

Abstract

The brine shrimp, Artemia franciscana, has a body plan composed of 11 thoracic segments, followed by 2 genital segments, and then 6 additional abdominal segments. Previous studies of Artemia reported that expression of the posterior-most Hox gene, Abdominal-B (Abd-B), is restricted to the genital segments and is not observed posteriorly in the abdomen at any developmental stage. This report was remarkable because it suggested that the Artemia abdomen posterior to the genital segments was a novel body region of 6 segments that bore no homology to any region in other crustaceans and was unique amongst arthropods in being a Hox-free segmented domain outside of the head. In this study, we used RT-PCR, antibody staining, and in situ hybridization on various stages of Artemia nauplii to show that Abd-B mRNA and protein are in fact expressed throughout the abdominal segments during Artemia development, but this expression later retracts to the two genital segments (G1, G2) and the T11 appendages. This suggests that Abd-B does play a role in specifying abdominal segment identity in all crustaceans that have been examined and suggests a common evolutionary origin for the crustacean abdomen.

Keywords: Abdomen; Abdominal-B; Artemia; Engrailed; Hox; Pancrustacea.

MeSH terms

Abdomen
Animals
Artemia* / genetics
Artemia* / metabolism
Gene Expression Regulation, Developmental
Homeodomain Proteins* / metabolism
Transcription Factors / metabolism

Substances

Homeodomain Proteins
Transcription Factors