1-Title: Sequence analysis and molecular characterization of TLR4 gene of camel (Camelus dromedarius)

1-Title: Sequence analysis and molecular characterization of TLR4 gene of camel (Camelus dromedarius)

Authors: Jyoti Choudhary, Mahender Milind, Mukul Purva, Aarti Nirwan, Monika Shekhawat and BN Shringi

Source: Ruminant Science (2022)-11(2):253-260.

How to cite this manuscript: Choudhary Jyoti, Milind Mahender, Purva Mukul, Nirwan Aarti, Shekhawat Monika and Shringi BN (2022). Sequence analysis and molecular characterization of TLR4 gene of camel (Camelus dromedarius). Ruminant Science 11(2):253-260.


Toll-like receptor 4 (TLR4) is essential for initiating the innate immune response to lipopolysaccharide from Gram-negative bacteria by acting as a signal-transducing receptor.  At present, there is a paucity of information about most of the dromedary camel (Camelus dromedarius) TLRs. We isolated the complementary DNA (cDNA) by RT-PCR and analysed the TLR4 sequence characters by bioinformatics tool. It was located on the 4th chromosome which had 3 exons. The complete mRNA sequence of the gene has been submitted in NCBI under accession number (MN807289), which was made up of 2936 bases long contig with 2526 long open reading frame (ORF) translated into 841 amino acids (aa) and consist of 20 types of aa. The camel TLR4 sequence had 97.03 per cent identity with the predicted TLR4 protein of dromedary camel with twenty-five additional AA which was justified by the newly updated predicted sequence (XM-010998309.2). TLR4 gene showed the highest degree of aa identity with pigs (83.59 %) whereas, lowest with the rabbit (69.64 %). The protein domain analysis predicted by bioinformatics consists of a transmembrane helices domain, eighteen leucine-rich repeat (LRR) domains, and a Toll/Interleukin-1 receptor (TIR) domain. The TIR domain for downstream signalling transduction was most conservative than other domains after the alignment of protein with different species.


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