Researchers from Stanford University have unearthed a plethora of microscopic entities residing within the human mouth and gut, aptly named "obelisks." These circular bits of genetic material, containing one or two genes, organize themselves into rod-like shapes, representing a mysterious addition to the realm of biological entities.

Although still in the preprint stage, this revelation has garnered significant attention, with mentions in prestigious journals like Nature and Science. The emergence of obelisks further complicates the understanding of the intricacies of life at the microscopic level. Even smaller than viruses are viroids; RNA molecules are devoid of protective shells yet are capable of causing severe plant diseases. 

The newly discovered obelisks blur the lines between viruses and viroids. With a circular single-stranded RNA genome akin to viroids but containing genes predicted to encode proteins like viruses, obelisks challenge conventional classifications. Named for their shape, "obelisks" leave room for interpretation, acknowledging their potential similarity to RNA plasmids.

Encoded within obelisks are unique proteins, primarily obulins, whose function remains elusive due to their lack of resemblance to known proteins. Using innovative techniques, the team identified nearly 30,000 distinct obelisk types from previously overlooked sources. The prevalence of obelisks across diverse environments, as evidenced by global datasets, suggests their ubiquity. While approximately 7% of gut microbiome datasets and 50% of mouth datasets contained obelisks, their true prevalence remains uncertain.

Moreover, the diversity of obelisk types among different body sites and individuals and the persistence of specific types over time raises intriguing questions about their role and significance within human microbiomes.

(Source:https://health.economictimes.indiatimes.com/news/industry/a-new-virus-like-entity-has-just-been-discovered-obelisks-explained/107455235?utm_source=top_story&utm_medium=homepage )