PT  - JOURNAL ARTICLE
AU  - Takayoshi Ishii
AU  - Martina Juranić
AU  - Shamoni Maheshwari
AU  - Fernanda de Oliveira Bustamante
AU  - Maximilian Moritz Vogt
AU  - Rigel Salinas-Gamboa
AU  - Steven Dreissig
AU  - Nial Gursanscky
AU  - Tracy How
AU  - Joerg Fuchs
AU  - Veit Schubert
AU  - Andrew Spriggs
AU  - Jean-Philippe Vielle-Calzada
AU  - Luca Comai
AU  - Anna M. G. Koltunow
AU  - Andreas Houben
TI  - Unequal contribution of two paralogous centromeric histones to function the cowpea centromere
AID  - 10.1101/2020.01.07.897074
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.01.07.897074
4099  - http://biorxiv.org/content/early/2020/01/08/2020.01.07.897074.short
4100  - http://biorxiv.org/content/early/2020/01/08/2020.01.07.897074.full
AB  - The legume cowpea (Vigna unguiculata, 2n=2x=22) has significant tolerance to drought and heat stress. Here we analysed and manipulated cowpea centromere-specific histone H3 (CENH3) genes, aiming to establish a centromere-based doubled-haploid method for use in genetic improvement of this dryland crop in future. Cowpea encodes two functional CENH3 variants (CENH3.1 and CENH3.2) and two CENH3 pseudogenes. Phylogenetic analysis suggests that gene duplication of CENH3 occurred independently during the speciation of V. unguiculata and the related V. mungo without a genome duplication event. Both functional cowpea CENH3 variants are transcribed, and the corresponding proteins are intermingled in subdomains of different types of centromere sequences in a tissue-specific manner together with the outer kinetochore protein CENPC. CENH3.2 is removed from the generative cell of mature pollen, while CENH3.1 persists. Differences between both CENH3 paralogs are restricted to the N-terminus. The complete CRISPR/Cas9-based inactivation of CENH3.1 resulted in delayed vegetative growth and sterility, indicating that this variant is needed for plant development and reproduction. By contrast, CENH3.2 knockout individuals did not show obvious defects during vegetative and reproductive development, suggesting that the gene is an early stage of subfunctionalization or pseudogenization.One-sentence summary The two paralogous centromeric histones (CENH3) of cowpea contribute unequal to the function of the centromere.