The role of chick Ebf genes in the mediolateral patterning of the somites

This study was conducted to check whether the three chick Early B‐cell Factor (Ebf) genes, particularly cEbf1, would be targets for Shh and Bmp signals during somites mediolateral (ML) patterning. Tissue manipulations and gain and loss of function experiments for Shh and Bmp4 were performed and the results revealed that cEbf1 expression was initiated in the cranial presomitic mesoderm by low dose of Bmp4 from the lateral mesoderm and maintained in the ventromedial part of the epithelial somite and the medial sclerotome by Shh from the notochord; while cEbf2/3 expression was induced and maintained by Bmp4 and inhibited by high dose of Shh. To determine whether Ebf1 plays a role in somite patterning, transfection of a dominant‐negative construct was carried out; this showed suppression of cPax1 expression in the medial sclerotome and upregulation and medial expansion of cEbf3 and cPax3 expression in sclerotome and dermomyotome, respectively, suggesting that Ebf1 is important for ML patterning. Thus, it is possible that low doses of Bmp4 set up Ebf1 expression which, together with Shh from the notochord, leads to establishment of the medial sclerotome and suppression of lateral identities. These data also conclude that Bmp4 is required in both the medial and lateral domain of the somitic mesoderm to keep the ML identity of the sclerotome through maintenance of cEbf gene expression. These striking findings are novel and give a new insight on the role of Bmp4 on mediolateral patterning of somites.     

Territory configuration moderates the frequency of extra‐group mating in superb fairy‐wrens

The frequency of extra‐pair paternity (EPP) in socially monogamous birds varies substantially between and within species, but ecological drivers of this variation remain poorly understood. Habitat configuration could influence EPP by moderating access to extra‐pair mates, because species occupying territories in a clustered ‘honeycomb’ configuration have a larger pool of potential extra‐group mates in their immediate neighbourhood than those living in linearly arranged territories (e.g. along narrow strips of riparian or fragmented habitat). We exploited variation in the spatial arrangement of territories due to anthropogenic modification of habitat of the cooperatively breeding superb fairy‐wren Malurus cyaneus to test whether habitat configuration influenced the frequency of EPP. In this species, most paternity is obtained by males outside the social group [extra‐group paternity (EGP)]. We found that the frequency of EGP among groups living in linear strips of roadside vegetation (41% of 44 offspring) was lower than it was for groups living in clustered territories within continuous habitat (59% of 70 offspring). Differences in group size and pair relatedness did not explain differences in EGP associated with territory configuration, although the frequency of EGP was negatively correlated with pair relatedness. Our finding suggests that territory configuration can influence rates of EGP and that anthropogenic habitat fragmentation has the potential to limit access to extra‐pair mates, affecting mating systems and ultimately fitness.     

Synthesis,Biological Evaluation,and Molecular Docking of Novel Thiazoles and [1,3,4]Thiadiazoles Incorporating Sulfonamide Group as DHFR Inhibitors

2‐(1‐{4‐[(4‐Methylphenyl)sulfonamido]phenyl}ethylidene)thiosemicarbazide ( 3 ) was exploited as a starting material for the synthesis of two novel series of 5‐arylazo‐2‐hydrazonothiazoles 6a  –  6j and 2‐hydrazono[1,3,4]thiadiazoles 10a  –  10d , incorporating sulfonamide group, through its reactions with appropriate hydrazonoyl halides. The structures of the newly synthesized products were confirmed by spectral and elemental analyses. Also, the antimicrobial, anticancer, and DHFR inhibition potency for two series of thiazoles and [1,3,4]thiadiazoles were evaluated and explained by molecular docking studies and SAR analysis.