1. How does X inactivation work? What are non-coding RNAs (ncRNAs)? What are ncRNAs not encoding? What are lncRNAs? Why would some people suggest to call these ncRNAs something else? Solution X inactivation is the process by which mammalian females inactivate one of their X chromosomes. The inactivation of one of the X chromosomes is highly complex. X inactivation is done by a transcription process. X inactivation uses RNAs and silencing enzymes. The silenced X chromosome condenses into a compact structure called the Barr body and is present in a silent state. Noncoding RNAs A non coding RNA is an RNA molecule that is not translated into proteins. Many noncoding RNAs may have functions other than protein formation in the cell. They may function in the regulation of gene expression. These functions may occur at the transcriptional level or at the post-transcriptional level. They also play an important role in heterchromatin formation, histones modification and gene silencing. Long noncoding RNAs (lnc RNAs) are believed to be involved in biological regulation including the developmental processes and formation of diseases. They are believed to be upregulated or downregulated in a number of diseases. However information about these RNAs is limited. The noncoding RNA are also called non-protein coding RNA, non-messenger RNA or functional RNA or even junk RNA. The noncoding RNA seem to have a housekeeping role in translation and splicing. Regulatory ncRNAs are involved in modification of other RNAs..

1. 1. How does X inactivation work? What are non-coding RNAs (ncRNAs)? What are ncRNAs
not encoding? What are lncRNAs? Why would some people suggest to call these ncRNAs
something else?
Solution
X inactivation is the process by which mammalian females inactivate one of their X
chromosomes. The inactivation of one of the X chromosomes is highly complex. X inactivation
is done by a transcription process. X inactivation uses RNAs and silencing enzymes. The
silenced X chromosome condenses into a compact structure called the Barr body and is present
in a silent state.
Noncoding RNAs
A non coding RNA is an RNA molecule that is not translated into proteins.
Many noncoding RNAs may have functions other than protein formation in the cell. They may
function in the regulation of gene expression. These functions may occur at the transcriptional
level or at the post-transcriptional level. They also play an important role in heterchromatin
formation, histones modification and gene silencing.
Long noncoding RNAs (lnc RNAs) are believed to be involved in biological regulation including
the developmental processes and formation of diseases. They are believed to be upregulated or
downregulated in a number of diseases. However information about these RNAs is limited.
The noncoding RNA are also called non-protein coding RNA, non-messenger RNA or functional
RNA or even junk RNA. The noncoding RNA seem to have a housekeeping role in translation
and splicing. Regulatory ncRNAs are involved in modification of other RNAs.