Transcription is the process by which segments of DNA are copied into RNA. Some of these segments encode proteins; others do not. These segments are referred to as messenger RNAs. A typical RNA sample contains between one and three percent of messenger RNA. To better understand the function of transcription, we can look at examples of RNA in nature.
Transcripts
Transcription is a process that transforms DNA segments into RNA. Specifically, transcription produces messenger RNA, a type of RNA that encodes proteins. Noncoding RNAs are also created, but these RNAs make up only a fraction of the total sample. Messenger RNA makes up 1% to 3% of the total RNA sample.
A transcription is a valuable tool for content creators and search engines. It makes content more searchable, which increases page rank for different types of keywords. In addition, it’s becoming increasingly common for video content creators to include transcripts used for closed captioning. This technology also helps make content more accessible to deaf, hard-of-hearing, and ESL audiences.
Transcription is also helpful for learning new languages, including dialects. For example, it’s often used in film scripts for historical films, as it shows how words have changed throughout the centuries and how to pronounce them in a given period. This is important, as languages do not stay the same, so even a few decades’ of pronunciation differences can change how a word sounds.
Editing
When editing your transcription, you should start by checking for errors. Many transcription services highlight low-confidence words, so you can quickly correct them. You can also use the “Seek and play” feature to start playback at a specific word in your transcription. This feature will save you time and help you navigate the transcript easily.
In addition to proofreading and editing, you should check for grammatical errors. These errors may sneak into your transcript if you don’t notice them immediately. Often, these mistakes occur because the speaker changes their thoughts mid-sentence. You can also check for homophones, words with the same meaning but spelled differently. For example, poor and pore are spelled differently but are not the same word. Also, do not break long words at the end of a line with hyphens. Instead, use hyphens to separate words with modifiers and compound words.
Termination
Termination of transcription is a process by which gene expression is terminated. It is carried out by RNA polymerase II (Pol II) and involves hundreds of thousands of transcription units. The termination process occurs in various ways and is highly responsive to various inputs. It may occur at the start of transcription or at a later time. Two commonly occurring forms of termination are promoter-proximal termination and premature termination. Both may regulate gene expression levels. However, research into these processes is still in its early stages.
The Pol II enzyme enables the termination of small noncoding RNAs. However, several mutations impair the activity of this enzyme. Mutations of the Pol II protein affect the elongation rate, altering the location of the termination window and disrupting the normal relationship between Pol II and the Sen1 helicase.
RNA polymerase
RNA polymerase is an enzyme that helps to transcribe DNA into RNA. This process is the first step in gene expression. It requires the cell to call over the enzyme to a region of the DNA called the promoter. Typically, the promoter region is called the TATA box in eukaryotic organisms. The enzyme then builds a new RNA strand using base pairing, adding nucleotides to the 3′ end of the strand.
The initiation of transcription is thought to be rate-limiting since it would be uncommon to find more than one polymerase engaged in a typical transcription unit. This conclusion is in contrastsidely held belief that transcription units are composed of many engaged enzymes.
Splicing
Splicing in transcription is an integral part of gene regulation. It allows a single gene transcript to be transcribed into different proteins in different tissues. This type of alternative splicing can be beneficial because it limits the pleiotropic effects of mutations on protein function. Moreover, tissue-specific alternative splicing promotes greater protein diversity.
This process generates proteins with distinct structural architectures. However, the differences in these proteins may not translate to functional specificities. However, several studies suggest that alternative splicing dramatically changes protein function. For example, the three-finger form of Drosophila transcription factor CF2 has different binding sites compared to the six and seven-finger forms.
The chromatoid body has also been suggested to be a splicing organelle. However, Biggiogera and colleagues have not yet confirmed this. Nevertheless, the discovery of pre-mRNAs in the chromatoid body adds to the arsenal of possible RNA processing components. In addition, it is worth noting that the chromatoid body is a highly evolved structure that has evolved to accommodate late spermiogenesis and nuclear quiescence.
