Concept explainers
To review:
The factor which triggers the early epigenetic modification in the chromatin of 3′ Hox genes which allows 3′ to 5′ loosening in chromatin states of Hox clusters over the course of paraxial mesoderm development. Whether additional regulators required to propel this transition to the 5′ end of the cluster. Also explain the mechanism that stablize the inheritance of epigenetic modification of Hox genes in a given segment.
Introduction:
The Hox genes are the important homeobox containing gene family which confer the positional information to the axial and paraxial tissues over the course of mesoderm development. These genes follow the sequential activation in time and space, and reflects their organization in clusters in the genome. The co-linearity of expression of Hox genes has been conserved during evolution, but not fully understood at molecular level. The somites resemble each other, but leads to the formation of different dtructures along the rostral to caudal axis.
Explanation of Solution
The anterior-posterior patterning of the somites is determines by the regulated expression of Hox genes. In more anterior regions of the paraxial mesoderm, the Hox genes present in the 3′ region of the genome cluster are likely to express. Whereas the genes present in the 5′ region likely to express in the posterior region. Any alteration in this Hox gene expression can leads to a change in specification of the mesoderm. The initiation of Hox gene expression is proposed by a progress zone model which explains the progressive activation of 3′ to 5′ Hox genes. This initial Hox transcription and the early rostral expansion of Hox expression domains depends upon the events which are related to the emergence and extension of the primitive streak. Wnt signaling may involve in the regulation of Hox gene expression during its anteriorward spreading. Fgf signalling also modulate the morphogenetic movement of the mesoderm, so also play an important role in the Hox gene expression. Retinoic acid (RA) also play a role in initiating Hox gene expression as RA is detected endogenously in the posterior part of early post-implantation embryos. Thus a number of signalling molecules progressively modulate Hox gene expression and also stabilize the epigenetic modification of Hox genes.
Thus it is concluded that the anterior-posterior patterning of the somites is determines by the regulated expression of Hox genes. Wnt signaling may involve in the regulation of Hox gene expression during its anteriorward spreading. Fgf signalling also modulate the morphogenetic movement of the mesoderm, Retinoic acid (RA) also play an important role in the Hox gene expression.
Want to see more full solutions like this?
Chapter 17 Solutions
Developmental Biology
- Lesson 2 Focus Questions 1. What chemicals and molecules are needed for PCR, and what is the function of each component? 2. Examine the 150 base promoter sequence below. Kaylee Kauff 5'TAGAAAAGGA AGGTGGCTCC TACAAATGCC ATCATTGCGA TAAAGGAAAG GTATCATTC AAGATGCCTC TGCCGACAGT GGTCCCAAAG ATGGACCCCC ACCCACGAGG AGC ATCGTGG AAAAAGAAGA CGTTCCAACC ACGTCTTCAA3' Write in the sequence of the complementary strand and mark the 3' and 5' ends of the complementary strand. 43arrow_forwardSCIENCE 9 WORKSHEET NO. 5-6 OUARTER 1- WEEKS 5-6 Problem Set Solve the following problems. 1. Show a cross between two heterozygous green pod and a homozygous yellow pad. 2. Show the cross between a homozygous constricted purple pod and a homozygous inflated yellow pod 3. What will be the genotype of the offspring if a cross between two heterozygous terminal purple flowers is done? 4. Show a cross between a heterozygous tall green plant and a homozygous short yellow plant. 5. Give the probability of having a heterozygous offspring if a cross between a heterozygous tall inflated pod plant and a homozygaus tall flat pod plant. 6. Acarrier of color blindness woman married a color- blind man. Is carrier offspring? 7. In cattle, the hornless condition (H) is dominant and the horned condition (h) is recessive. A bull without horns is crossed with a cow with harns. Of the four offspring, one (1) is horned and three (3) are hornless. Determine the genotype of the bull and the cow. 8. In…arrow_forwardNeed help Q1: Assuming these two genes sort independently, how many progeny would you expect to show the green striped phenotype? (Enter your answers as a whole number, e.g. 1) Q2: Which of the following are recombinant phenotypes? (Select all that apply) A. Green and Spotted B. Green and Striped C. Yellow and Spotted: D. Yellow and Stripedarrow_forward
- ARTER 1 WEEK 5- WEEK 6 WRITTEN WORKS (30% OF YOUR GPAD ANSWER THE EOU E Learning Task 5: Read and understand the pattern of inheritance in multiple alleles. Answer the guide question in your notebook. Multiple Alleles Mendel studied just two alleles of his pea genes, but real populations of- ten have multiple alleles of a given gene, In this activity you will learn how to crossed the gene for coat color in rabbits (the C gene) which comes in four color alleles (C, Cch, Ch, c) as shown by the figure De below. Pe e ALBNO ACH CHINTHLLA HAILAYN Using the given genotypes, find the Fl and F2 generation of the crossed between black rabbit and chinchilla, the crossed of himalayan and albino. Use the Punnet squares below to guide you. A. Black (CC) x Chinchilla (CchCch) F1 Offspring with corresponding % Fa Offspring with corresponding % Guide Question 1. Based on the results of the genetic crosses you have shown, how do you think the red and white flower alleles can "interact with one another?…arrow_forwardQuestion:- The success of renal transplantation depends on three human histocompatibility genes, HLA-A, HLA-B and HLA-C, which must match between the donor and the receiver. A single mismatch may cause the kidney rejection. Each gene has multiple co-dominant alleles. These three genes are located very close to each other on chromosome 6, so that the recombination rate is very low (below 1%). The father has the following genotype: A1, A2, B24, B10, Cw4 and Cw7 and the mother is A1, A1, B11, B7, Cw5 and Cw8. Their first boy is A1, A1, B24, B11, Cw7 and Cw8. What is the probability that the second child is compatible with his/her brother?arrow_forwardNeed help 1a. The blue gene 'Abd-B' in Drosophilais is [homologous] to blue #9 gene in Mus musculus? A. orthologous B. paralogous C. analogous 1b. Is the yellow gene 'Antp' in Drosophila more related (have higher similarity of genetic sequence) with the orange gene 'Scr' in Drosophila or with the yellow gene '#6' in any of the Hox clusters in Mus musculus A. there is not enough information to make this determination B. yellow gene '#6' in any of the Hox clusters in Mus musculus C. orange gene 'Scr' in Drosophilaarrow_forward
- URGENT Occasionally, a mouse X chromosome is broken into two pieces and each piece becomes attached to a different autosome. A scientist studies this cell, and finds that the genes on only one of the two pieces undergo inactivation. By referring to the mechanism of X-chromosome inactivation, explain the observation made by the scientist.arrow_forwardQuestion: What is a loss of function of a certain protein that prevents nucleotide metabolism and prevents DNA synthesis - this gene is expressed in all tissues but is expressed at the highest levels in bone marrow?arrow_forwardTask #1 Mc1r alleles: In Florida Gulf coast mice, there are two different alleles of the Melanocortin Receptor (Mcr1) gene. The sequence for both alleles is shown below. This is an internal segment of the coding (non-template) sequence of the Mcr1 gene. The reading frame is set and you do not need to find an AUG. M allele 5’...ATC ACC AAA AAC CGC AAC CTG CAC TCG... m allele 5’...ATC ACC AAA AAC TGC AAC CTG CAC TCG... A. Compare these two allele sequences and circle the nucleotides that are different. B. Do you think this change will cause a shift in the codon reading frame? Why or why not? C. Do you think that this change will cause an early stop in translation? Why or why not? Task #2 Flow of information: A codon table is provided above. The 5’ codon nucleotide is in the left column, and second codon nucleotide is on top. The Mcr1 M and m allele sequences are shown again in the central dogma grids below with the reading frame designated. Fill in the grids. In the second column…arrow_forward
- LEARNING TASK 1 "BIKINI BOTTOM GENETICS" Use the information for SpongeBob's traits to write the phenotype (physical appearance) for each item. Trait Dominant Gene Recessive Gene PHENOTYPE Body Shape SquarePants (S) Round pants (s) Body Color Yellow (Y) Blue (y) Eye shape Round (R) Oval (r) Nose Style Long (L) Stubby (1) LEARNING TASK 2 Use the information in Learning Task 1 to write the genotype (or genotypes) for each trait below. (a) Yellow body (b) Roundpants (e) Stubby nose - (f) Round eyes - (g) Squarepants - (h) Blue body - (c) Oval eyes - (d) Long nose - Determine the genotypes for each using the information in Learning Task 1. (a) Heterozygous Round Eyes (b) Homozygous Long Nose (c) Purebred Squarepants (d) Hybrid Yellow bodyarrow_forwardProblem Question The pedigree in one family with an inherited disorder affecting the nervous system is shown in Fig. 1. Ő IV V ||| sopisin mob I Fig. 1 Disease pedigree in one family. Five generations I, II, III, IV and V are shown. Females are represented by circles, males by squares, sex unknown by a diamond and deceased by a diagonal line through the symbol. Filled symbols indicate that the individual displays the disease phenotype; unfilled symbols indicate that the individual is unaffected. Carriers are not indicated. No information on disease status is available for generation I. 1. Which pattern(s) of Mendelian inheritance is (are) suggested by the pedigree in Fig. 1? Clearly explain your reasons for selecting and eliminating particular inheritance patterns.arrow_forwardNeed help fast What molecular mechanisms operate to ensure that once the decision to advance through the restriction point has been made, this leads to an essentially irreversible commitment to complete the remaining phases of the cell cycle through M phase?arrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning