Sulfolobus solfataricus Has Nucleolus-like Structures Involved in Ribosome Formation

Posted on May 17, 2023 • 2 minutes • 347 words

Sulfolobus solfataricus is an archaeon that belongs to the phylum Crenarchaeota and is known for inhabiting acidic hot springs. One of the most striking features of this microorganism is the absence of a formed nucleus within its cell. However, recent studies have shown that ribosome formation happens on similar structures named nucleolus. This is a surprising discovery because the nucleolus is a hallmark of eukaryotic cells, which have a well-defined nucleus. The nucleolus is a subnuclear organelle that is responsible for the synthesis of ribosomal RNA (rRNA) and ribosome assembly. It is composed of three main components: the fibrillar center (FC), the dense fibrillar component (DFC), and the granular component (GC). These components have distinct functions in the process of ribosome formation and maturation.

In Sulfolobus solfataricus, the nucleolus-like structures have been observed using electron microscopy and immunolabeling techniques. The components of these structures are morphologically similar to those found in eukaryotic nucleoli. However, there are some differences in the organization and composition of the FC, DFC, and GC. For example, the FC in Sulfolobus nucleolus-like structures is less defined than in eukaryotes, and the GC is more electron-dense.

The nucleolus-like structures in Sulfolobus solfataricus are involved in the synthesis and maturation of ribosomes. The rRNA genes are located on the genome in clusters, and transcription of these genes occurs in the nucleolus-like structures. The rRNA is then processed and assembled with ribosomal proteins to form functional ribosomes. The ribosomes are essential for protein synthesis, and because of this process, Sulfolobus solfataricus is capable of thriving in extreme environments like hot springs.

In conclusion, the discovery of nucleolus-like structures in Sulfolobus solfataricus has shed light on the evolution of ribosome formation in archaea and eukaryotes. The lack of a formed nucleus in archaea like Sulfolobus solfataricus does not impede the formation and assembly of ribosomes. The nucleolus-like structures in Sulfolobus solfataricus have similar functions to those found in eukaryotes, but with some unique differences. Understanding the mechanisms of ribosome formation in archaea and eukaryotes could have important implications for the development of new antibiotics and antimicrobial agents.