Describe the similar seasonal changes between the butterfly in Florida and the butterfly in Wyoming during

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. And the antigens that represent a danger induces an immune response by stimulating the lymphocytes to produce antibody or to attack the antigen directly. 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+) and the activation of important signaling cascades within the lymphocytes. 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, some receptors such as the TCR have ITAM sequences that, when activated, trigger an intracellular reaction based on consecutive phosphorylations. 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, and relieves the inhibition of the transcription factor which regulates genes that are involved in the immune reaction.

6 0

2 years ago

Which part of the microscope is used to make small adjustments in the image of an object?

Rus_ich [418]

Answer:

The part of the microscope that is used to make small adjustments in the image of an object is the fine adjustment.

Explanation:

In the optical microscope, the fine adjustment knob allows precise focusing of the sample being studied. This means making minimal adjustments in order to better observe the microscopic image.

After the initial focusing with the coarse adjustment knob, with the fine adjustment it is possible to highlight the details that require more attention, as well as the refringency of the sample, if it exists.

The other options are not correct because:

A. Eyepiece is the lens that receives the image from the objective lens, that has contact with the eyes of the observer.

C. Coarse Adjustment is the rough magnification, used for the initial approximation of the image.

D. Objective lens enlarges and defines the image of the sample on the slide.

6 0

3 years ago

The term “seafloor spreading" is best used to describe-*

frutty [35]

Answer:

magma upwelling and lateral expansion along the mid-Atlantic ridge

Explanation:

8 0

2 years ago

A primipara tells the nurse that her baby is breathing very rapidly and that the breaths are irregular. she expresses fear that

Nastasia [14]

For a nurse it is quite normal because she knows the pattern of breathing of a small baby but for a primipara ( a lady who is giving birth for the first time ) it might not be acceptable to understand the fact that a newly born baby has an irregular breathing pattern switching in between fast and slow .

As she is a new mother she might not be aware of the fact that a baby breathes very fastly to compensate the amount of energy required to maintain the homeostasis of the baby.As the baby is in growing stage the amount of energy required is much more as compared to that of adults.

Hence , the nurse will not take any medical action as the baby is not sick but yes she will definitely tell the mother that it is normal in baby

4 0

2 years ago

Read 2 more answers

These jars show the set-up from Francesco Redi's experiment with meat and maggots. After a few days of sitting out, the covered

padilas [110]

C. the flies could not get into the jar to lay their eggs

6 0

3 years ago