JaMBW Chapter 2.1
Reverse, Complement, Inverse
Aim
Given a sequence of nucleic acids, this program generates its
reverse, its complement, and its inverse into three independent
windows. The above mentioned terminology is explained with the
following example:
5' ATATATCCCGGCG 3' input sequence
5' GCGGCCCTATATA 3' its reverse
5' TATATAGGGCCGC 3' its complement
3' TATATAGGGCCGC 5' its inverse (say, reverse and complement)
Mode of operation
This program uses 4 windows: the top one should be filled from
the user, with a sequence of interest, while the other 3 windows
contain the results of the operations. The following steps must
be performed:
- Sequence input
- Symbols used
Either paste or type in the top area the sequence of interest.
Any character or symbol that does not belong to the IUB [atcgATCG]
set is ignored.
- removal of header information
Only the sequence must be placed in the top window: heading comments
must be removed
- long sequences and small window
In order to allow users with small screens to still be able of
using this program, the size of each window had been made rather
small. Therefore, use the scroll-bars in order to move around
in the input and output windows. The suggested strategy is to
double click in the specified area and then do copy/paste from/to
the text-editor of choice or across different applications.
- Case sensitivity choice
Often is useful to mark regions of interest by changing the Case.
This applet is capable of keeping those modifications also in
its output, as well as to change the case of the sequence according
to your wish. Therefore, by selecting anyone of the 3 choices
provided, and hereafter described, the user has control on this
aspect. In order to choose the case in the output, the following
selections are possible, by clicking on the button close to them:
- Unchanged, leaves the same case in the output as in
the input, and is useful for easier identification of already
marked regions in the sequence
- Upper, generates as output the upper case conversion
(e.g. atcg becomes ATCG)
- Lower, generates as output the lower case conversion
(e.g. ATCG becomes atcg)
-
- Convert
Once the sequence is placed in the top window, by pressing the
"CONVERT" button then the conversion is performed.
How to understand its output
Since both aim and mode of operation are rather straightforward,
also the understanding and the use of the results from this work
should not present any major difficulty. The output will simply
consist of the same sequence reverse, complemented and inverted
as in the examples shown above.
References
- Watson,J.D. and Crick,F.H.C.(1953) Genetical implications
of the structure of deoxyribonucleic acid. Nature,171,964-967.
- Nomenclature Committee of the International Union of Biochemistry
(NC-IUB) (1985) Nomenclature for incompletely specified bases
in nucleic acid sequences. Recommendations 1984.Eur-J-Biochem,150,1-5
Author:Luca I.G. TOLDO,
Edition date: 28 February 1997