Extended Data Fig. 1: ECS1 and ECS2 are specifically expressed in the egg cell of Arabidopsis.
From: Fertilized egg cells secrete endopeptidases to avoid polytubey
a, Fragments per kilobase of transcript per million mapped reads (FPKM) values (Mean ± s.d.) of ECS1 and ECS2 transcripts in egg cells and zygotes. RNA-seq data of Ec, Zy 1C and 32C are from ref. 41 except 8C (GSE33713), seedlings (GSE32318), stems (GSE102694), roots and rosettes (GSE87760). b–i, Promoter activity analysis using the nuclear marker H2B–GFP expressed by ECS1 (b–e) and ECS2 (f–i) promoters, respectively. Both promoters were specifically active in egg cells after embryo sac cellularization. b, f, Female gametophyte before cellularization. c, g, Immature egg cell. d, h, Mature egg cell. e, i, Zygote at 20 HAP. 1C, 1-cell pro-embryo; 8C, 8-cell pro-embryo; 32C, 32-cell embryo; n, nucleus; ecn, egg cell nucleus; syn, synergid cell nucleus; zy, zygote. Dashed lines outline the egg cell and zygote, respectively. Insets show enlargements of regions indicated. Scale bars, 20 μm.
