Reverse transcriptase (RNA-dependent DNA polymerase)
A reverse transcriptase gene is usually indicative of a mobile element such as a retrotransposon or retrovirus. Reverse transcriptases occur in a variety of mobile elements, including retrotransposons, retroviruses, group II introns, bacterial msDNAs ...
A reverse transcriptase gene is usually indicative of a mobile element such as a retrotransposon or retrovirus. Reverse transcriptases occur in a variety of mobile elements, including retrotransposons, retroviruses, group II introns, bacterial msDNAs, hepadnaviruses, and caulimoviruses.
Telomeres in most organisms are comprised of tandem simple sequence repeats [1]. The total length of telomeric repeat sequence at each chromosome end is determined in a balance of sequence loss and sequence addition [1]. One major influence on telome ...
Telomeres in most organisms are comprised of tandem simple sequence repeats [1]. The total length of telomeric repeat sequence at each chromosome end is determined in a balance of sequence loss and sequence addition [1]. One major influence on telomere length is the enzyme telomerase [1]. It is a reverse transcriptase that adds these simple sequence repeats to chromosome ends by copying a template sequence within the RNA component of the enzyme [1]. The RNA binding domain of telomerase - TRBD - is made up of twelve alpha helices and two short beta sheets [2]. How telomerase and associated regulatory factors physically interact and function with each other to maintain appropriate telomere length is poorly understood. It is known however that TRBD is involved in formation of the holoenzyme (which performs the telomere extension) in addition to recognition and binding of RNA [2].
The RRM motif (a.k.a. RRM, RBD, or RNP domain) is probably diagnostic of an RNA binding protein. RRMs are found in a variety of RNA binding proteins, including various hnRNP proteins, proteins implicated in regulation of alternative splicing, and pro ...
The RRM motif (a.k.a. RRM, RBD, or RNP domain) is probably diagnostic of an RNA binding protein. RRMs are found in a variety of RNA binding proteins, including various hnRNP proteins, proteins implicated in regulation of alternative splicing, and protein components of snRNPs. The motif also appears in a few single stranded DNA binding proteins. The RRM structure consists of four strands and two helices arranged in an alpha/beta sandwich, with a third helix present during RNA binding in some cases The C-terminal beta strand (4th strand) and final helix are hard to align and have been omitted in the SEED alignment The LA proteins (Swiss:P05455) have an N terminal rrm which is included in the seed. There is a second region towards the C terminus that has some features characteristic of a rrm but does not appear to have the important structural core of a rrm. The LA proteins (Swiss:P05455) are one of the main autoantigens in Systemic lupus erythematosus (SLE), an autoimmune disease.
