Background/Purpose:

Sjögren’s syndrome is a complex autoimmune disease of the salivary gland with an unknown etiology, so a thorough characterization of the transcriptome would facilitate our understanding of the disease. We used ultra-deep sequencing of small RNAs of human salivary glands to identify and discover novel miRNA sequences that may play a role in the disease and validated the presence of those novel miRNAs in other human tissues.

Methods:

Total RNA was isolated from minor salivary glands of healthy volunteers and patients with either high or low salivary flow. The sequencing was performed on the SOLiD platform (Applied Biosystems), using their Small RNA Expression Kit protocol, which selectively enriches small RNAs (< 300 bp).  These sequencing reads were mapped to three different databases, and if reads matched to any of the databases were removed. The unmapped sequences were subsequently examined for other characteristics of microRNA, such as the loop formation of the premicroRNA, with the web-based algorithm miRanalyzer. The novel sequences that possessed the characteristics of microRNAs were subsequently validated with custom desgined TaqMan probes, in several human tissue (bladder, brain, lung, ovary, kidney, adipose tissue, spleen, colon, placenta, thymus, liver and testes total RNA) and a new cohort of minor salivary gland RNA from healthy volunteer and Sjögren’s syndrome patients).

Results:

There were 121,148 (patient – high flow), 52,568 (patient – low flow), and 174,482 (Healthy Volunteer) unique reads that matched to the human genome. These genome-matched reads generated a total of 222 predicted mature miRNAs. Following the selection process, we identified 44 candidates. Of these candidates, 16 had variable expression among the different human tissues and some of them were differentially expressed between Sjogren’s syndrome and healthy control salivary glands.

Conclusion:

Sequencing small RNAs in the salivary glands has not been extensively and systematically performed. Our work not only identified novel microRNAs, but also identified differentially expressed microRNAs between healthy controls and Sjögren’s syndrome patients

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« Back to 2013 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/discovery-and-validation-of-novel-micrornas-in-minor-salivary-glands-of-sjogrens-syndrome-patients/