Sisilamma GeorgeLIJO JOHN2020-07-072020-07-072011http://krishikosh.egranth.ac.in/handle/1/5810148732A study has been carried out to analyse the promoter and 3’UTR of hsp70gene in different breeds of chicken (Naked neck (NaNa), Kadaknath (KAD), White Leghorn (WL), Rhode Island Red (RIR) and White Plymouth Rock (WPR)) and duck (Kuttanadu (KUT) and White Pekin (WP)). Plasma corticosterone level was also estimated in two different (summer and rainy) seasons. Promoter and 3’ UTR of Hsp70 gene were amplified by PCR and the products were sequenced. Sequence analysis of the promoter region showed 100% homology between three breeds of chicken, WL, RIR and KAD and the duck breeds. These breeds exhibited only 99.7% identity with WPR and NaNa Sequence alignment (with Gene bank accession no. J02579) revealed a point mutation in the CAAT box, where an ‘A’ is deleted at position -312 in all the breeds of chicken and duck except NaNa. Another ‘A’ deletion could also be detected at position -329 from a heat shock element in WPR. In all the breeds under study, TATA box (TATAA) was found at position -134. Three inverted CAAT boxes, ‘ATTG’ and two variants of GC boxes, one having GGCG motif (6 numbers) and another having GGGCGG motif (2 numbers) were identified in both chicken and duck sequences. Two variants of consensus heat shock elements (HSE), NGAAN (single unit) and ‘NGAAGAAN’ (double unit) were detected in the promoter region of all breeds of chicken and duck under study except WPR, in which a point mutation (‘A’ deletion) was noted in one of the double units. Restriction analysis showed that only Bgl І has a site in the amplified region of the promoter of both the species. Due to the presences of point mutations, three alleles for the promoter region of the gene could be detected. Sequence analysis of 3’ UTR showed varying levels of sequence polymorphism between chicken breeds, where only 80 to 95.8 % identity could be observed. Between duck breeds, KUT and WP, 97.7 % identity was observed. Analysis between chicken and duck revealed 79 to 99.5% identity where 97 to 99.5% identity was observed between duck breeds and WPR. Two consensus, CAAC sequence and a variant of poly adenylation signal sequence could be identified in 3’ UTR. A variant of poly adenylation signal sequence, TATAAA could be identified in all breeds except RIR, in which two point mutations (transversion) were observed (TAAAAA) when compared to the consensus sequence (AATAAA). A second poly adenylation signal sequence, which was again a variant (AATAAT) was detected only in NaNa. The number and position of CAAC motifs varied (2 to 4 numbers) between species and breeds under study. In both the species, rather than a consensus sequence, a variant of K box (GGTGAT) and Brd box (TGCTTA) could be identified. Several AT (AU in mRNA) rich regions could be identified in the 3’ UTR of both chicken ad duck breeds. However, an additional ATATA motif is also detected in RIR and NaNa. Restriction enzyme analysis of 3’ UTR revealed that NaNa, RIR and WL have no cutting site for any of the common enzymes while a single cutting site for Bgl ІІ was observed in KAD, showing two alleles in chicken breeds. Duck breeds also showed two alleles where the enzyme, Bam HI has a restriction site at different positions. Plasma corticosterone level in chicken and duck showed considerable variation in different breeds of chicken both in summer and rainy seasons. Among the chicken breeds WPR showed the lowest level of corticosterone in summer season, which did not differ significantly from that of rainy season. Comparison between seasons showed a highly significant (P<0.01) increase in summer in all breeds except WPR. Duck breeds also showed a similar trend. Significant (P<0.01) increase in the plasma corticosterone level was noticed in summer. However, between breeds, no significant variation was observed in each season. Hormone responsive elements (HRE) for corticosterone could not be detected in the promoter region of any of the breeds under study. Any correlation between the sequences and the plasma corticosterone level could not be detected in both chicken and duck breeds under study. Although, two point mutations were detected in the promoter region of WPR, it could not be correlated with the plasma corticosterone level.ennullThesis