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#117148 - 04/14/18 03:03 PM Re: Journal papers online - reference list [Re: Wieslaw]
Redcap Offline
Ruler of the Roost

Registered: 08/14/06
Posts: 985
Loc: Germany
Maybe the hedgehog signaling pattern in relation to cyclopamine-sensitive signals controls beak deformity as well?!
Quote:
But this study show that the lateral and longitudinal morphology of the single-comb is established under the regulation of a cyclopamine -sensitive signal from E4 to E7. The number and appearance of the comb serration are under the regulation of similar signals and the patterning occurs in an anterior to posterior direction.

Cross reference to the hedgehog signaling pattern
http://www.the-coop.org/forums/ubbthreads.php?ubb=showflat&Number=112391#Post112391

Edit: See this study about beak deformities through cyclopamine.
Cordero, D., Marcucio, R., Hu, D., Gaffield, W., Tapadia, M., & Helms, J. A. (2004). Temporal perturbations in sonic hedgehog signaling elicit the spectrum of holoprosencephaly phenotypes. Journal of Clinical Investigation, 114(4), 485494.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC506789/


Edited by Redcap (04/14/18 05:59 PM)
Edit Reason: Added the Cordero study
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#117149 - 04/15/18 12:02 AM Re: Journal papers online - reference list [Re: Redcap]
Wieslaw Offline
Moderator
Classroom Professor

Registered: 09/18/09
Posts: 3840
Loc: Denmark
Narrowing the wingless-2 mutation to a 227 kb candidate region on chicken chromosome 12.

https://www.ncbi.nlm.nih.gov/pubmed/29562287

Abstract

Quote:
Wingless-2 (wg-2) is an autosomal recessive mutation in chicken that results in an embryonic lethal condition. Affected individuals exhibit a multisystem syndrome characterized by absent wings, truncated legs, and craniofacial, kidney, and feather malformations. Previously, work focused on phenotype description, establishing the autosomal recessive pattern of Mendelian inheritance and placing the mutation on an inbred genetic background to create the congenic line UCD Wingless-2.331. The research described in this paper employed the complementary tools of breeding, genetics, and genomics to map the chromosomal location of the mutation and successively narrow the size of the region for analysis of the causative element. Specifically, the wg-2 mutation was initially mapped to a 7 Mb region of chromosome 12 using an Illumina 3 K SNP array. Subsequent SNP genotyping and exon sequencing combined with analysis from improved genome assemblies narrowed the region of interest to a maximum size of 227 kb. Within this region, 3 validated and 3 predicted candidate genes are found, and these are described. The wg-2 mutation is a valuable resource to contribute to an improved understanding of the developmental pathways involved in chicken and avian limb development as well as serving as a model for human development, as the resulting syndrome shares features with human congenital disorders.

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#117151 - 04/16/18 12:54 PM Re: Journal papers online - reference list [Re: Wieslaw]
Redcap Offline
Ruler of the Roost

Registered: 08/14/06
Posts: 985
Loc: Germany
Fattahi S, Pilehchian Langroudi M, Akhavan-Niaki H. (2018). Hedgehog signaling pathway: Epigenetic regulation and role in disease and cancer development. J Cell Physiol. March 2018;110.
http://documents.kippenjungle.nl/#post57
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#117172 - 05/13/18 09:00 PM Re: Journal papers online - reference list [Re: Redcap]
KazJaps Offline
Classroom Professor

Registered: 08/30/02
Posts: 2864
Loc: Australia
May 2018 Study /review on the GHR gene biology and mutations causing dwarfism in both humans and chickens

Lin, S.; Li, C.; Li, C.; Zhang, X. Growth Hormone Receptor Mutations Related to Individual Dwarfism. Int. J. Mol. Sci. 2018, 19, 1433.

Abstract excerpts...
http://www.mdpi.com/1422-0067/19/5/1433
Quote:
Until now, more than 90 GHR mutations relevant to human short stature (Laron syndrome and idiopathic short stature), including deletions, missense, nonsense, frameshift, and splice site mutations, and four GHR defects associated with chicken dwarfism, have been described. Among the 93 identified
mutations of human GHR, 68 occur extracellularly, 13 occur in GHR introns, 10 occur intracellularly, and two occur in the transmembrane. These mutations interfere with the interaction between GH and GHRs, GHR dimerization, downstream signaling, and the expression of GHR.

*Full paper pdf download link available on above web page.

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#117313 - 11/01/18 04:20 PM Re: Journal papers online - reference list [Re: KazJaps]
Wieslaw Offline
Moderator
Classroom Professor

Registered: 09/18/09
Posts: 3840
Loc: Denmark
https://www.ncbi.nlm.nih.gov/pubmed/30124802

Gonadal and Endocrine Analysis of a Gynandromorphic Chicken.

Quote:

Quote:
Abstract
Birds have a ZZ male and ZW female sex chromosome system. The relative roles of genetics and hormones in regulating avian sexual development have been revealed by studies on gynandromorphs. Gynandromorphs are rare bilateral sex chimeras, male on one side of the body and female on the other. We examined a naturally occurring gynandromorphic chicken that was externally male on the right side of the body and female on the left. The bird was diploid but with a mix of ZZ and ZW cells that correlated with the asymmetric sexual phenotype. The male side was 96% ZZ, and the female side was 77% ZZ and 23% ZW. The gonads of this bird at sexual maturity were largely testicular. The right gonad was a testis, with SOX9+ Sertoli cells, DMRT1+ germ cells, and active spermatogenesis. The left gonad was primarily testicular, but with some peripheral aromatase-expressing follicles. The bird had low levels of serum estradiol and high levels of testosterone, as expected for a male. Despite the low percentage of ZW cells on that side, the left side had female sex-linked feathering, smaller muscle mass, smaller leg and spur, and smaller wattle than the male side. This indicates that these sexually dimorphic structures must be at least partly independent of sex steroid effects. Even a small percentage of ZW cells appears sufficient to support female sexual differentiation. Given the lack of chromosome-wide dosage compensation in birds, various sexually dimorphic features may arise due to Z-gene dosage differences between the sexes.

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#117314 - 11/04/18 04:54 AM Re: Journal papers online - reference list [Re: Wieslaw]
Wieslaw Offline
Moderator
Classroom Professor

Registered: 09/18/09
Posts: 3840
Loc: Denmark
Just as a curiosity

Zygotic gene activation in the chicken occurs in two waves, the first involving only maternally derived genes.

https://www.ncbi.nlm.nih.gov/pubmed/30375976

Quote:
Abstract
The first-wave of transcriptional activation occurs after fertilisation in species-specific patterns. Despite its importance to initial embryonic development, the characteristics of transcription following fertilisation are poorly understood in Aves. Herein, we report detailed insights into the onset of genome activation in chickens. We established that two waves of transcriptional activation occurred after fertilisation and at Eyal-Giladi and Kochav Stage V. We found 1,544 single-nucleotide polymorphisms across 424 transcripts derived from parents in offspring during the early embryonic stages. Surprisingly, only the maternal genome was activated in the zygote, and the paternal genome remained silent until the second-wave, regardless of the presence of a paternal pronucleus or supernumerary sperm in the egg. The identified maternal genes involved in cleavage were replaced by bi-allelic expression. The results demonstrate that only maternal alleles are activated in the chicken zygote upon fertilisation, which could be essential for early embryogenesis and evolutionary outcomes in birds.

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