The three-dimensional conformation of a protein may be strongly influenced by amino acid residues that are very far apart in sequence. This relationship is in contrast to secondary structure, where the amino acid residues are:

#Question id: 2972

#Unit 2. Cellular Organization

Match the following attachment (Column I) with definition(Column II).

Which of the following is correct?

#Question id: 2973

#Unit 2. Cellular Organization

Following statements are regarding to the spindle position checkpoint pathway in budding yeast.

A. During interphase and early mitosis, Cdc14 is sequestered and inactivated in the nucleolus. Inactive Tem1-GDP associates with the spindle pole body (SPB) nearest to the bud as soon as the mitotic spindle forms.

B. If chromosome segregation occurs properly, extension of the spindle microtubules inserts the daughter SPB into the bud, causing Tem1 to be activated by an unknown mechanism.

C. Tem1-GDP activates a protein kinase cascade, which then promotes the release of active Cdc14 from the nucleolus and exit from mitosis.

D. If the spindle apparatus fails to place the daughter SPB in the bud, Kin4 (cyan), an inhibitor of Tem1, is recruited from the parent cell cortex to the parent-cell-located SPB and maintains Tem1 in the GTP-bound form, and mitotic exit does not occur.

Which of the following are correct?

#Question id: 2974

#Unit 2. Cellular Organization

Following statements are regarding to control of the G1–S phase transition in budding yeast.

A. G1 cyclin-CDK complexes stimulate the formation of G1/S phase cyclin-CDKs, which then initiate bud formation, centrosome duplication, and DNA replication. In yeast, the G1 cyclin gene is called CLN3.

B. Once sufficient Cln3 is synthesized from its mRNA, Cln3-CDK complexes phosphorylate and activate the transcriptional repressor Whi5.

C. Phosphorylation of Whi5 promotes its export out of the nucleus, allowing the transcription factor complex SBF to induce transcription of the G1/S phase cyclin genes CLN1 and CLN2 as well as other genes important for DNA replication.

D. Once produced, Cln1/2-CDKs contribute to further Whi5 phosphorylation. This positive feedback loop ensures the rapid accumulation of G1/S phase cyclin-CDKs.

Which of the following statements are correct?

#Question id: 2975

#Unit 2. Cellular Organization

Following statements are regarding to the Surveillance mechanisms in cell cycle regulation.

A. Surveillance mechanisms known as checkpoint pathways establish dependencies among cell cycle events and ensure that the next cell cycle event does not occur prior to the completion of a preceding event.

B. In response to DNA damage, two related protein kinases, ATM and ATR, are recruited to the site of the damage, where they activate signaling pathways that lead to cell cycle arrest, repair, and under some circumstances, apoptosis.

C. The spindle assembly checkpoint pathway, which causes initiation of anaphase, utilizes Mad2 and other proteins to regulate APC/CCdc20, which targets securing and mitotic cyclins for ubiquitinylation.

D. The spindle position checkpoint pathway prevents mitotic CDK inactivation when the spindle is mispositioned. In this pathway, localized activators and inhibitors and a sensor that shuttles between them allow cells to sense spindle position.

Which of the following statement is incorrect?

#Question id: 2976

#Unit 2. Cellular Organization

Match the following Regulators with its functions.

Which of the following is correct?

#Question id: 2977

#Unit 2. Cellular Organization

The mitotic exit network that localizes to spindle pole bodies and whose activity is regulated by spindle position belongs to the family of signaling pathways known as the Hippo pathway in metazoans. Following statements are-

A. The conserved core of the Hippo signaling pathways consists of the Hippo protein kinase, which activates the Lats-Mob1 kinase.

B. The kinases are organized by a scaffolding molecule that, at least in budding and fission yeasts, targets the kinase cascade to centrosomes.

C. As in many kinase signaling cascades, a GTPase controls the activity of the mitotic exit network and the septation initiation network.

D. In metazoans, activation of the Hippo pathway leads to tissue overgrowth because the transcriptional activator TAZ (known as YAP in the mouse) constitutively promotes the expression of growth- and proliferation-promoting genes.

Which of the following statements are incorrect?