The core smooth muscle enriched transcriptome

Smooth muscle fibers are composed of smooth muscle cells attached to each other via gap junctions. They are found throughout the body, around blood vessels and hollow organs. They have a synchronized response to stimuli, producing pressure through involuntary muscle contraction, allowing them to perform essential bodily functions, such as the regulation of blood pressure.

In this section we detail the predicted core smooth muscle cell transcriptome, highlighting genes classified as having predicted specificity in smooth muscle cells in multiple tissue types. Such genes could be useful general markers for smooth muscle cells across tissue beds, and are likely critical for smooth muscle specific functions. These genes are sub-divided into 3 categories, based on the number of tissues in which they were independently classified as smooth muscle cell enriched.

Smooth muscle cells were profiled in 10 of the tissues featured in the Tissue Cell section.

• 10 genes predicted as enriched in smooth muscle cells in 75-100 % tissues
• 34 genes predicted as enriched in smooth muscle cells in 50-75 % tissues
• 79 genes predicted as enriched in smooth muscle cells in 25-50 % tissues

Protein expression of genes enriched in smooth muscle cells across tissue types

An example of a protein with enriched expression in smooth muscle cells across multiple tissue types is calponin 1 (CNN1), which is a thin filament-associated protein implicated in the regulation and modulation of cell contraction.

CNN1 - Colon
CNN1
CNN1 - Lung
CNN1
CNN1 - Prostate
CNN1
CNN1 - Skeletal muscle
CNN1

Another example of a protein with enriched expression in smooth muscle cells across multiple tissue types is Leiomodin 1 (LMOD1), a member of the actin filament nucleator family.

LMOD1 - Lung
LMOD1
LMOD1 - Prostate
LMOD1
LMOD1 - Adipose subcutaneous
LMOD1

Genes enriched in smooth muscle in the bronchus include Caldesmon 1 (CALD1), a protein implicated in the regulation of actin and myosin interactions.

CALD1 - Lung
CALD1

Genes with predicted specificity in smooth muscle cells in individual tissues

A summary table of all genes with predicted high enrichment in smooth muscle cells in profiled tissues is provided below. Identified genes are subdivided into 3 categories in each tissue, based on the difference between the enrichment score in smooth muscle cells, compared to the other cell types profiled (see Methods Summary page for details):

• Predicted specificity: ´Very high´ - Differential score vs. other profiled cell types within the tissue >0.35
• Predicted specificity: ´High´ - Differential score vs. other profiled cell types within the tissue >0.25
• Predicted specificity: ´Moderate´ - Differential score vs. other profiled cell types within the tissue >0.15

Table 1: Genes predicted to be enriched in smooth muscle cells by tissue type