TY - JOUR
T1 - Characterization and Transformation of reg Cluster Genes in Volvox powersii Enable Investigation of Convergent Evolution of Cellular Differentiation in Volvox
AU - Grochau-Wright, Zachariah I.
AU - Ferris, Patrick J.
AU - Tumberger, John
AU - Jiménez-Marin, Berenice
AU - Olson, Bradley J.S.C.
AU - Michod, Richard E.
N1 - Funding Information: We would like to thank Telsa Mittelmeier, Carol Dieckmann, Hope Dang, David Shahnooshi, Sudhir Nayak, Nina Peel, and Gary Dickinson for technical assistance and sharing of space or resources. We are grateful to Hisayoshi Nozaki for providing us with the WT V. powersii strain. We also thank Gavriel Matt, James Umen, Dinah Davison, Lisa Nagy and Stephen Miller for useful discussions and feedback. Funding for this work was provided by the National Aeronautics and Space Administration (grant NNX13AH41G), Howard Hughes Medical Institute Inclusive Excellence grant GT11065 to The College of New Jersey, and the National Science Foundation (grants MCB-1412395 and DEB 2029999). Finally, we are sad to note that our co-author Dr. Patrick Ferris passed away while this manuscript was undergoing peer review. His work, mentorship and expertise was invaluable to completing the research presented here and we include him as a co-author posthumously. Publisher Copyright: © 2021 Elsevier GmbH
PY - 2021/10/1
Y1 - 2021/10/1
N2 - The evolution of germ-soma cellular differentiation represents a key step in the evolution of multicellular individuality. Volvox carteri and its relatives, the volvocine green algae, provide a model system for studying the evolution of cellular differentiation. In V. carteri, the regA gene controls somatic cell differentiation and is found in a group of paralogs called the reg cluster, along with rlsA, rlsB, and rlsC. However, the developmental program of V. carteri is derived compared to other volvocine algae. Here we examine Volvox powersii which possesses an ancestral developmental program and independent evolution of the Volvox body plan. We sequenced the reg cluster from V. powersii wild-type and a mutant with fewer cells and altered germ-soma ratio. We found that the mutant strain's rlsB gene has a deletion predicted to cause a truncated protein product. We developed a genetic transformation procedure to insert wild-type rlsB into the mutant strain. Transformation did not result in phenotypic rescue, suggesting the rlsB mutation is insufficient for generating the mutant phenotype. The transformation techniques and sequences described here provide essential tools to study V. powersii, a species well suited for studying the evolution of cellular differentiation and convergent evolution of Volvox morphology.
AB - The evolution of germ-soma cellular differentiation represents a key step in the evolution of multicellular individuality. Volvox carteri and its relatives, the volvocine green algae, provide a model system for studying the evolution of cellular differentiation. In V. carteri, the regA gene controls somatic cell differentiation and is found in a group of paralogs called the reg cluster, along with rlsA, rlsB, and rlsC. However, the developmental program of V. carteri is derived compared to other volvocine algae. Here we examine Volvox powersii which possesses an ancestral developmental program and independent evolution of the Volvox body plan. We sequenced the reg cluster from V. powersii wild-type and a mutant with fewer cells and altered germ-soma ratio. We found that the mutant strain's rlsB gene has a deletion predicted to cause a truncated protein product. We developed a genetic transformation procedure to insert wild-type rlsB into the mutant strain. Transformation did not result in phenotypic rescue, suggesting the rlsB mutation is insufficient for generating the mutant phenotype. The transformation techniques and sequences described here provide essential tools to study V. powersii, a species well suited for studying the evolution of cellular differentiation and convergent evolution of Volvox morphology.
KW - VARL genes
KW - Volvocine algae
KW - genetic transformation
KW - germ-soma differentiation
KW - multicellularity
KW - reg cluster
UR - http://www.scopus.com/inward/record.url?scp=85117582351&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85117582351&partnerID=8YFLogxK
U2 - 10.1016/j.protis.2021.125834
DO - 10.1016/j.protis.2021.125834
M3 - Article
C2 - 34695730
SN - 1434-4610
VL - 172
JO - Protist
JF - Protist
IS - 5-6
M1 - 125834
ER -