design: RNA-seq data of barley embryos of wild-type 'Sebastian' and double mutant hvcbp20.ab/hvcbp80.b under control conditions and in the presence of 75 µM ABA
library_construction_protocol: We followed the protocol described in Peirats-Llobet et al. (2023). At 1 DAI (days after imbibition), embryos were isolated from the germinating seeds using a scalpel, and the embryonic root was removed. The embryos were embedded in an optimal cutting temperature (OCT) medium and frozen in an isopentane bath on dry ice. The frozen samples were stored at –80°C until further processing. Sections of 10 µm thickness were prepared using a cryostat (Leica CM3050 S) at –18°C. Two control embryo sections and three ABA embryo sections were placed on Visium Spatial Gene Expression Slide. Slides were fixed in chilled methanol for 30 min in –20°C. After fixation, sections were stained for 5 min with 0.1% Safranin O (Sigma-Aldrich, cat. no. S8884-25G) in 50% ethanol. The sections were then washed in an alcohol series (50%, 70%, 100%) for 1 min . Slides were imaged in the bright field using a light microscope (Leica DS5500) for downstream spatial transcriptomic analysis. Seeds were sterilized in a 20% sodium hypochlorite solution for 20 minutes and then thoroughly washed three times with sterile water for 5 minutes. After sterilization, seeds were placed in Petri dishes (⌀ = 90 mm) on three layers of Whatman filters with 5 ml of distilled water (control) or a distilled water containing 75 µM ABA solution (cis–trans-abscisic acid; Sigma-Aldrich, catalog no. 862169). The seeds were stratified in darkness at 4°C for 4 days and then transferred to a growth chamber  (22°C, 16-h-light/8-h darkness, 200 μmol/m−2 s−1 illumination).  RNA was isolated using the RNeasy Mini Kit (Qiagen) according to the manufacturer's instructions. RNA integrity was assessed using an Agilent 2100 Bioanalyzer to determine the RNA Integrity Number (RIN).  cDNA libraries were prepared using the Visium Spatial Gene Expression protocol (10x Genomics). Poly-A mRNA was captured and reverse-transcribed to generate cDNA, which was subsequently amplified and indexed for sequencing.