(A) Frozen liver tissue is cut and placed on a special slide special slide
covered by beads carrying capture oligos composed by a polyd(T) tail for RNAs
capture, a spatial barcode defining bead position, an UMI for transcript count,
promoters and adaptors for cDNA synthesis, amplification and sequencing and a
cleavage site to detach the oligos from the slide. B) The liver tissue on the
spatial transcriptomics slide is fixed, stained by H&E and scanned by a
conventional microscopy slide scanner. The tissue is lysed to release RNA, the
capture oligos are cleaved and the libraries prepared as for scRNA-seq. The
H&E image combined with data and coordinates of the spatial barcodes produce
high-resolution single-cell gene expression data. GLUL encoding for
glutamate-ammonia ligase is a known pericentral zonated gene and PCK1 encoding
for phosphoenolpyruvate carboxykinase 1 is a periportal zonated gene. cDNA,
complementary DNA; scRNA-seq, single-cell RNA-sequencing; UMI, unique molecule
identifier.