Segmentation genes

The basic steps of gene cloning first involve cutting a precise DNA segment (gene) from a donor source DNA by use of a restriction enzyme (Figure 45.2). At the same time, a small looped... 

Howard, K., and Ingham, P. (1986). Regulatory interactions between the segmentation genes fushi tarazu, hairy and engrailed in the Drosophila blastoderm. Cell 44 949-957. 

Langhon, A., and Scott, M. P. (1984). Sequence of a Drosophila segmentation gene protein structure homology with DNA-binding proteins. Nature 310 25-31. 

Emx genes are important for the genesis of the hippocampus (Pellegrini et ah, 1996) and point mutations of Emx2 are associated with schizencephaly (Brunelli et ah, 1996). Thus, these homologues of early segmentation genes in Drosophila serve fundamental functions in the development in the human brain. 

Maternal-Effect Gene Products for Oocytes Are Frequently Made in Helper Cells Gap Genes Are the First Segmentation Genes to Become Active... 

Gap Genes Are the First Segmentation Genes to Become Active... 

The gap gene products regulate the position-specific expression of other genes, those belonging to the pair-rule class of segmentation genes. 

Based only on the definition of maternal-effect genes, segmentation genes, and homeotic genes, which do you predict act earliest in development of the Drosophila embryo, and which act latest ... 

Cutting DNA at precise locations to yield the DNA segment (gene) of interest by use of sequence specific restriction endonuclease (restriction enzyme). 

Figure 33.17. V( D ) J Recombination. The heavy-chain locus includes an array of 51 V segments, 27 D segments, and 6 J segments. Gene rearrangement begins with D-J joining, followed by further rearrangement to link the V segment to the DJ segment.

Many of the segmentation genes that determine the periodic subdivisions of the ectoderm are also involved in generating the mesodermal A and P domains, as well as in the resulting diversification of tissues in the trunk mesoderm. For example, mutations in pair-rule genes that reduce the number of ectodermal parasegments in half also produce half the number of mesodermal parasegments. Notably, null mutations... 

Wimmer, E., Jackie, H., Pfeifle, C., and Cohen, S. (1991). A Drosophila homologue of human Spl is a head-specific segmentation gene. Nature 366 690-694. 

Myasnikova, E., A. Samsonova, K. Kozlov, M. Samsonova, and J. Reinitz. 2001. Registration of the expression patterns of Drosophila segmentation genes by two independent methods. Bioinformatics 17 3-12. 

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