Which of the following statements is correct?

Following antigenic stimulation, phosphorylation of _________ relieves inhibition of the transcription factor

Maru [420]

Answer: zap70, ITAM.

Explanation:

An antigen is any substance that is capable of stimulating an immune response by activating lymphocytes, which are the body’s infection-fighting white blood cells. Examples of antigens could be proteins that are part of bacteria or viruses or components of serum and red blood cells from other individuals, all of them are foreign antigens originated outside the body. However, there can also be autoantigens (which are self-antigens), originated within the body. In normal conditions, the body is able to distinguish self from nonself. <u>And the antigens that represent a danger induces an immune response by stimulating the lymphocytes to produce antibody or to attack the antigen directly</u>. This is called an antigenic stimulation of the immune system.

ZAP-70 (Zeta-chain-associated protein kinase 70) is a protein that is part of the T cell receptor, thereby it plays a critical role in T-cell signaling. When the TCR (receptor of T cells) is activated by the presentation of the specific antigen through the MHC, a protein called Lck acts to phosphorylate the intracellular CD3 chains and the ζ chains of the TCR complex, allowing the binding of the cytoplasmic tyrosine kinase, ZAP-70. Lck then phosphorylates and activates ZAP-70, which in turn phosphorylates another molecule in the signaling cascade called LAT (short for Linker of Activated T cells), a transmembrane protein that serves as an anchor site for several other proteins. The tyrosine phosphorylation cascade initiated by the Lck culminates in the intracellular mobilization of calcium ion (Ca2+) <u>and the activation of important signaling cascades within the lymphocytes.</u> These include the Ras-MEK-ERK pathway, which is based on activating certain transcription factors such as NFAT, NFκB and AP-1. These transcription factors regulate the production of of certain gene products, most notably cytokines such as interleukin-2 that promote the long-term proliferation and differentiation of activated lymphocytes.

The ITAM motifs (immunoreceptor tyrosine-based activation motif) are sequences of four amino acids present in the intracellular tails of certain proteins that serve as receptors within the immune system. Thus, <u>some receptors such as the TCR have ITAM sequences that, when activated, trigger an intracellular reaction based on consecutive phosphorylations</u>. Kinases are recruited for this purpose.

So, ZAP-70 is a protein tyrosine kinase with a role in T-cell receptor signal transduction. During T-cell activation, ZAP-70 binds to ITAM and becomes tyrosine phosphorylated. The binding of ZAP-70 to the phosphorylated ITAM is able to activate its kinase activity, <u>and relieves the inhibition of the transcription factor which regulates genes that are involved in the immune reaction</u>.

6 0

3 years ago

100 POINTS IF CORRECT!!!

Yuliya22 [10]

From a Punnett square you can get the genotypic and phenotypic proportions of the progeny produced from a cross. Cross: PpRr x PpRr. F1: PPRR, PPRr, PPRr, PPrr, PpRr, Pprr, ppRR, ppRr, pprr.

<h3>What is a Punnett square?</h3>

The Punnett square is a graphic representation that shows the different types of gamete combinations according to the alleles involved in a cross.

Punnett square shows the probabilities of getting offspring with different genotypes and their consequent phenotypes.

In the exposed example, we know that two genes are involved in the cross.

As we can see, there are dominant and recessive alleles for both genes.

Since each genotype in the square results from the combination of parental gametes, we can figure out which are the parental genotypes.

For instance, let us consider the provided genotypes

PPRr.

We can assume one of the parents provided a P and a R dominant alleles, while the other parent provided another P allele but a r recessive allele.

PR + Pr ⇒ PPRr

ppRr.

One of the parents provided a p recessive allele and a R dominant allele, The other parent provided another p allele and a r recessive allele.

pR + pr ⇒ ppRr

pprr.

Both parents provided p and r recessive alleles.

pr + pr ⇒ pprr

From this information, we can assume parents are heterozygous for both genes.

Cross:

Parentals) PpRr x PpRr

Gametes) PR, Pr, pR, pr PR, Pr, pR, pr

Punnett square) PR Pr pR pr

PR PPRR PPRr PpRR PpRr

Pr PPRr PPrr PpRr Pprr

pR PpRR PpRr ppRR ppRr

pr PpRr Pprr ppRr pprr

F1) 1/16 individuals are expected to be PPRR

2/16 individuals are epected to be PPRr

1/16 individuals are expected to be PPrr

2/16 individuals are expected to be PpRR

4/16 individuals are expected to be PpRr

2/16 individuals are expected to be Pprr

1/16 individuals are expected to be ppRR

2/16 individuals are expected to be ppRr

1/16 individuals are expected to be pprr

For a better understanding, you will find the Punnett square in the attached files representing the parental gametes with different colors, and the resulting genotypes with a combination of these colors.

In this way, you will notice which gamete comes from which parent.

You can learn more about Punnett squares at

brainly.com/question/25357981

#SPJ1

5 0

1 year ago

The hormone insulin is produced by what organ in the body?.

fiasKO [112]

Answer:

pancreas

Explanation:

I am 95% sure

8 0

3 years ago

Read 2 more answers

What must plants be able to do

Jet001 [13]

What makes plants special is that they produce their own food. Leaves capture the sunlight in order to do this. They contain a pigment called chlorophyll, which makes the leaves green. Using carbon dioxide, water, nutrients, and energy from sunlight, the chlorophyll makes the food that the plant needs.

3 0

3 years ago

Transverse tubules Select one: a. store sodium ions for the action potential at the cell surface. b. transmit muscle impulses in

otez555 [7]

Answer:

b. transmit muscle impulses into the cell interior.

Explanation:

Transverse Tubules are also known as T Tubes that pass laterally through the muscle fiber. The T Tubes or Transverse Tubules carry the nerve impulses received by the sarcolema to the myofibrils, these are also conductive to substances such as glucose, oxygen and ions. In other words, these tubules are responsible for transmitting muscle impulses into the cell interior.

8 0

3 years ago