Nelisäikeisen

Nelisäikeisen is a Finnish term that translates to "four-stranded" or "quadruple-stranded" in English. It is primarily used in a biological context to describe molecular structures composed of four intertwined strands. The most common and significant application of this term is in relation to DNA and RNA.

In molecular biology, DNA typically exists as a double helix, meaning two complementary strands wind around each other. However, under certain conditions, and in specific biological contexts, DNA can form a quadruple helix, also known as a G-quadruplex. These G-quadruplex structures are formed in guanine-rich sequences and are stabilized by Hoogsteen hydrogen bonds. The term "nelisäikeisen" can be used to refer to these G-quadruplex structures, highlighting their unique four-stranded nature. These structures are found in telomeres, promoter regions of genes, and other areas of the genome, and are thought to play roles in gene regulation, replication, and maintenance of genomic stability.

Similarly, RNA can also form four-stranded structures, although they are less common and less well-studied than DNA G-quadruplexes. The term "nelisäikeisen" could also be applied to these RNA quadruplexes. Research into these nelisäikeisen structures is ongoing, with scientists investigating their formation, function, and potential as therapeutic targets in various diseases.