Three classes of hemoglobins are required for optimal vegetative and reproductive growth of Lotus japonicus: Genetic and biochemical characterization of LjGlb2-1

Villar, I. ; Rubio, M.C. ; Calvo-Begueria, L. ; Pérez-Rontomé, C. ; Larrainzar, E. ; Wilson, M.T. ; Sandal, N. ; Mur, L.A. ; Wang, L. ; Reeder, B. ; Duanmu, D. ; Uchiumi, T. ; Stougaard, J. ; Becana, M.

Resumen: Legumes express two major types of hemoglobins, namely symbiotic (leghemoglobins) and non-symbiotic (phytoglobins), with the latter being categorized into three classes according to phylogeny and biochemistry. Using knockout mutants, we show that all three phytoglobin classes are required for optimal vegetative and reproductive development of Lotus japonicus. The mutants of two class 1 phytoglobins showed different phenotypes: Ljglb1-1 plants were smaller and had relatively more pods, whereas Ljglb1-2 plants had no distinctive vegetative phenotype and produced relatively fewer pods. Non-nodulated plants lacking LjGlb2-1 showed delayed growth and alterations in the leaf metabolome linked to amino acid processing, fermentative and respiratory pathways, and hormonal balance. The leaves of mutant plants accumulated salicylic acid and contained relatively less methyl jasmonic acid, suggesting crosstalk between LjGlb2-1 and the signaling pathways of both hormones. Based on the expression of LjGlb2-1 in leaves, the alterations of flowering and fruiting of nodulated Ljglb2-1 plants, the developmental and biochemical phenotypes of the mutant fed on ammonium nitrate, and the heme coordination and reactivity of the protein toward nitric oxide, we conclude that LjGlb2-1 is not a leghemoglobin but an unusual class 2 phytoglobin. For comparison, we have also characterized a close relative of LjGlb2-1 in Medicago truncatula, MtLb3, and conclude that this is an atypical leghemoglobin. © 2021 The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Idioma: Inglés

DOI: 10.1093/jxb/erab376

Año: 2021

Publicado en: Journal of Experimental Botany 72, 22 (2021), 7778-7791
ISSN: 0022-0957

Factor impacto JCR: 7.378 (2021)

Categ. JCR: PLANT SCIENCES rank: 15 / 240 = 0.062 (2021) - Q1 - T1

Factor impacto CITESCORE: 10.9 - Biochemistry, Genetics and Molecular Biology (Q1) - Agricultural and Biological Sciences (Q1)

Factor impacto SCIMAGO: 1.913 - Plant Science (Q1) - Physiology (Q1)

Financiación: info:eu-repo/grantAgreement/ES/DGA/A09-20R
Financiación: info:eu-repo/grantAgreement/ES/MCIU/RYC2018-023867-I
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2020-113985GB-I00
Financiación: info:eu-repo/grantAgreement/ES/MINECO/AGL2017-85775--R
Financiación: info:eu-repo/grantAgreement/ES/MINECO/BES-2015-073059
Financiación: info:eu-repo/grantAgreement/ES/MINECO/RTI2018-094623-B-C22

Tipo y forma: Article (Published version)